I live in SF because I grew up here and have family around, not because I think it's "better" than other places to live. If I weren't so anchored here, I'd probably look around. That said, I like it a lot more than the OP here...

* I think the food options in SF are actually pretty excellent. I'm going to agree that "late dinner" options are limited - I guess I just see that as a relevant but not defining criteria. Options at the low and medium price range tend to fall at various ethnic eateries or small, neighborhood restaurants, and the remarkable diversity of SF does make for a lot of good options (see below). The 15-20 seat restaurant where dinner for two + wine ranges from $80-120 is probably where SF excels the most.

* Astounding diversity. I read a while back a list of cities with languages spoken by 1000 or more households. SF actually came in first, with 6. This shows in the number of different ways you can eat for under $7.

* It's truly beautiful in many ways. There's no way to list all the views, but here are a few of my favorites: twin peaks, coit tower, the library at UCSF, the legion of honor museum (the golden gate bridge and marin headlands), the tower at the de young (outer sunset, golden gate park to ocean beach)... well, this is where SF gets an A+.

* On a smaller level, SF is both beautiful and horrible. I avoid the really touristy spots (including, sadly, north beach, though I do like it in small doses). I like walking the neighborhoods: cole valley, fillmore, hayes valley, chestnut, cortland, noe... even if some of them are a bit yuppy and others are a little blighted. That said, the OP is absolutely correct that once you move your gaze from the beautiful views and (at times overly quaint) neighborhoods, the city is blighted and filthy in many ways, and the local populace seems far less willing than NY or Chicago to do something about it.

* Local outdoors: crissy fields, golden gate park, land's end, the presidio... and if you want a short drive, you can be in the middle of a quiet redwood forest in about half an hour. The Olympic peninsula is, ultimately, a more impressive sight than Point Reyes, but I do think you can pass through more different ecosystems in Sonoma County (thick forests, sand dune beaches, marshes, etc...) In Golden Gate park, the blight is unfortunately part of the experience as well. Recently, a couple of pit bulls ran wild and bit a few people before the police shot them. Maybe some day, if the city does turn this around, this will be a story we tell about our low points (like the stories you hear about Central Park in the 70s). Maybe dirty harry can come out of retirement, heh.

* Do you surf? (or other ocean sports). It's cold, but the quality to crowd ratio remains pretty good.

* Public transportation - not great, I don't think it's quite as bad as the OP states. If it goes where you're going, it's ok. BART and Muni are reasonably fast and direct provided you are underground. Express buses are also pretty quick and good. But if you aren't on a direct like, yeah, you're hosed. Add in the fact that SF is (I believe) the most densely populated city west of the mississippi, and you have to drive and park... u, talk about the worst of both worlds. If there's one thing that makes me wish I didn't live here, this is it. I set my life up so that I am one one of those direct bart/muni lines.

* Rockin' baseball park. One of the best. I don't miss candlestick at all. Actually, the embarcadero has emerged as a pretty fun stroll from the ferry building to the ballpark (it was just a big freeway when I was a kid).

* Neat other stuff: San Francisco is preservation minded to a fault, and this has at times hurt the city. But still, we do run those cable cars, and while they are overpriced, they're neat. More amusingly, SF has restored it's own old (1930s) trolly cars, and, having run out of old cute stuff to restore, went around the world to find other cities' old trolly cars and got them running too (1890s - 1940s). Want to see what street cars used to look like in London, Tokyo, or Milan? Come on out to SF, we'll restore your old junk for you. And unlike the cable cars, we don't charge tourist prices to ride them, it's just like any other bus or train.

* UCSF's mission bay campus is going to make a serious impact on this world. Any time someone tells you SF is only preservation minded, ask them if innovation comes in the form of skyscrapers or cutting edge biotech research. Ok, the answer is both, but don't mistake SF's hostility (which I admit is excessive) to changing the physical environment with a parochial backwoodsyness. This is probably the most common accusation, and it's at least 60% untrue.

I actually tried to leave SF. I missed my family, but it was more than that. But what can I say, I guess I just have to stay here. As a final note, there isn't much local snobbery in SF, other than a few bozos who like to start sentences with "as a 3rd generation san franciscan" (as if this somehow increases the relevance of their opinion?) San Franciscans like newcomers. However, they will want you to stay, especially if you have kids, and they can get peevish if you plan to leave ;)