In the games industry, .dds's and .tga's are pretty common (from my experience) since they have high quality - though .dds's don't have support for alpha channels. The .png format is supposed to retain a really high quality from source work, and it also supports an alpha channel.
I've never worked directly with the .png format, though I have a little experience with .dds's. I'd say, just from my usage of the format, .tga is the best one I've used so far... as mentioned though, I'm not sure how that applies to ultra-high-res, doesn't-need-to-be-30+fps rendering.