There's nothing more subjective than talking about which anime you like and which you hate, but that doesn't mean it isn't fun to do anyway. Just keep in mind my opinions are worth about what the electrons they're printed on cost, and that when I'm talking about a series being a 'loser' that's only in my book and your mileage will vary.
Winner - Sora no Manimani
The character designs somehow screamed "aimed at little kids" to me, but that's not true - this has turned out to be my favorite series of the summer, although I didn't expect it to be. A story about a high school astronomy club may not sound interesting on paper, but I give them a lot of credit - there's a solid cast and this always manages to put a smile on my face. The basic storyline is our hero, Saku, returns to a town he lived in as a child after moving all over the place, and is reunited with his hyper-genki, star-loving childhood friend Mihoshi - throw in a couple other bishoujo and supporting characters, add the cast growing up and starting to fall in love for the first time, stir, and you've got a surprisingly funny series. Hime especially cracks me up, her reactions to other girls getting close to Saku are priceless.
Loser - Suzumiya Haruhi no Yuutsu
I never in a million years thought I would drop Haruhi - after waiting so long for a second season, and having loved the first season, this should have been an easy winner, but I honestly can't bring myself to watch Sighs. It doesn't help that Sighs was the novel I enjoyed the least, and obviously Endless Eight is Endless didn't help. I dropped this after the third Endless Eight iteration, picked it back up when Sighs started, then dropped it again. Sighs just really doesn't make Haruhi very likeable, and I think she's at her best when she does show a bit of humanity under the tsun-tsun exterior. Not to mention pathetic-mode Mikuru just makes me want to smack her and tell her to stop whining and grow some balls, being afraid Haruhi will make the world end if you stand up to her is no excuse for not having a spine.
Winner - Yoku Wakaru Gendai Mahou
I know, the first episode had as much nopan as Saki, so how can anyone take this seriously? I've never believed that fanservice = bad series - I've loved series that have no service at all, and I've loved series that have tons of it. To me, what matters most is a good cast, and the cast of Gendai Mahou keeps me watching. Yes, Yumiko is an ojou-sama stereotype, and Koyomi has more in common with Fuuko than her voice actress, but they make a good team, and I think when they're on screen together is really when this is the most fun to watch. The plot makes very little sense, the animation's uneven, but the story of Yumiko making a good friend and Koyomi gaining more confidence just makes it impossible for me not to root for them both. And no, I don't mean in the yuri sense, although if they went there I wouldn't complain.
Loser - Princess Lover
Bishoujo series, even though some fans look down on them, to me can be really good - Kanon, Da Capo, Lamune, there are plenty of examples of the genre that I really enjoyed. Princess Lover isn't one of them. First, I admit it's a shallow reason, but the character designs just kill me, specifically the fact the whole female cast is like an X-cup. I know anime dimensions don't correspond to reality, but there's a fine like between big breasts and grotesquely oversized breasts, and Charlotte's J-cup knockers fall in the latter category for me. In real life, her spine would snap from the weight of those gazoombas. Add to that the fact it can't seem to decide what the hell it is - is this a comedy like the onsen episode? Action series like the car chase in the first episode? Some series can do everything well, but this can't. The onsen episode was mildly amusing, but honestly Fumoffu did it much better. Dropped after it started turning into a Die Hard sequel, with Charlotte trapped in the building.
Winner - Taishou Yakyuu Musume
Honestly, the background music for this series sounds like it's out of a Tom and Jerry cartoon half the time, but aside from that, it's got me hooked with a great cast and a fun, laid-back story. I wrote about it earlier, and since then it's kept my interest well - some episodes are stronger than others, but it's fun to watch, and honestly that's the main thing I look for in anime. I'm also impressed that it's taken a pretty realistic approach - the girls don't suddenly level up and beat all the guys' teams to a pulp the next day, they're still practicing, struggling to beat elementary school kids, and learning what it's like to play as a team.
Loser - Kanamemo
It has Hocchan in it, it has good character designs, moe aplenty, and a slice-of-life feel to it - Kanamemo is the story of a group of girls who deliver newspapers, with their boss improbably being a loli in elementary school. It also sucks in my book not because it has a lot of fanservice (censored in the TV and Crunchyroll broadcast) but because the characters just don't do a lot for me and the 'comedy' always fails to make me laugh. Hocchan's character just grabs Kana's non-existent boobs all the time. The 'Chief' is an elementary school girl. Kana herself is so naive she must have been locked in a back room in her grandmother's house for the last ten years. There are lesbians and some other characters, but honestly none of them really makes me want to watch this. Mika is a typical Kugimiya Rie character, which is fine since although they get a lot of hate tsunderes are still entertaining for me, but she's a loli too and doesn't get that much screentime. Worst of all, though, is the swimsuit episode where everyone bursts into song, like they're gunning for Best Musical suddenly - if I could forget one episode of anime this season, just completely wipe it out of my memory for all eternity, that episode would be it.
Winner - Gintama
Gintama's one of those series I go back and forth on - some episodes are pure toilet humor and I stop watching halfway through, but then the next episode will have me laughing my ass off. I re-watched episode 88 the other day, and no matter how many times I see Zura rapping, or the 'filthy Tower of Babel' it just cracks me up. I'm not sure how funny it would be if you don't know the characters from watching it all along, but episode 88 is probably one of the top 10 anime episodes of all time for me, when it comes to pure comedy.
Loser - Umi Monogatari
Great character designs, scores high on the bishoujo scale, decent animation - but I still couldn't keep my eyes open four episodes in. Relaxing gondola-rowing type music during fight scenes is just not a good idea, and the plot is pretty mediocre. I know, I watch Gendai Mahou so I shouldn't complain about plot, but I think again it's the cast of Umimono that lost me the most - Marin is ultra-optimistic but just comes across to me as an airhead, while other hyper-genki characters this season like Mihoshi at least promise to show some depth too. And Urin...worst name for an anime character of all time.