I only came across this by chance on a news group, but there is a version of Picasa available for Linux. That fact isn't obvious from the main Picasa home page. People tell me that Picasa isn't bad, but I wasn't interested in it while I thought it was Windows only. What Google has done is to get it working under Wine, rather than recode it for Linux. I've downloaded it, and it certainly has no problem reading the RAW files from my Fujifilm S3 Pro digital SLR. I'll definitely be playing with it to see what it can do. I'm not sure how the performance under Wine will be, that's an open question.
One things I've noticed, though, it that it appears to want to import all of my photos into its own folder, rather than allowing them to be left in place. My RAW files are 24-26MB each, so I don't want multiple copies of them on my drive if I can avoid it. It will depend on whether I think Picasa is good enough to make the sacrifice and do it Google's way.