After listening to some new stuff for the first time in ages starting in June, thanks to a tip from Surrel about Animal Collective, I've sort-of developed my own short list of Best Bands in this category.
First, by a big margin, is Animal Collective. However, I've also learned they tend to be a pretty divisive band - you either think they're great, or you think they're awful. Haven't found many people in the middle ground, though I'm sure they exist.
Second is Grizzly Bear. They're almost the opposite of AnCo. Whereas AnCo usually tries to cram every millisecond with as much sound as they think they can get away with, Grizzly Bear's songs are usually pretty sparsely arranged. Even the louder songs often sound a bit "minimalist" (for lack of a better word).
Third is Tame Impala. Main reason they're third at this point, however, is because they've only done 2 albums so far. But also because, I suppose, their sound is highly derivative, moreso than most other bands around these days. That said, they do a superb job of deriving.
I'll put Atlas Sound at a distant 4th. The guy who does Atlas Sound also has a band Deerhunter, but I prefer his solo stuff better. Haven't really been able to get into Deerhunter. In fact I gave away their latest album to someone after trying to listen to it a few times.
Other than those, the only band that has caught my attention so far is Deerhoof. Deerhoof is definitely ... gee I dunno ... creative? Definitely an entertaining listen but I'm not sure I'd actually want to buy one of their albums.