I bought one of the 2 lense kits(14-45 & 40-150mm) for $810 at Best Buy(financed, score one for the broke dude!). I'm really enjoying it so far, camera feels great in my hands and feels solid despite the plastic body. Its really light for a dSLR, some people may appreciate that, but I would like a bit more weight. Takes the same batteries that the C5060,7070,8080s use, so I was square with that. It has two card slots, one for FC and another for XD - just like the PnS models already noted. The viewfinder is kinda small, but more than ample. All the exposure controls are at hand without going into the menu(short of the ISO which has its own button into the menu). Manual WB can be done without accessing the menu. Dust will never be a problem on the lense.
As of yet, I'm not aware of a housing for it. Although, I wouldn't be able to afford it if it were to come out anytime soon anyway
I've read that Olympus will be bringing 3 more dSLR bodies to the market in 2006. The E1's successor is rumored to be in the mix, not sure what else. I'm hoping nothing that will make the E500 obsolete, if so, ah well - I'm happy regardless. Olympus is planning on jumping its sales in the dSLR level from 3% to 30% within the next 5 years - so expect alot to be coming out.