The 350D looks like a great camera. But I fear that there will be few housings built for it (although I guess that Ikelite might be an exception). We have been rather spoilt over the last few years with housings being available for just about every Canon and Nikon DSLR to hit the market. Now that the market is starting to mature I think that economics of underwater photography (there aren't really that many of us really) will make it pointless to house certain models (the Fuji S3 is another that will probably get few housings despite it having some great features for UW shooting).
My concern with the 350D is that it is too similar to the 20D. Which is already out and with housings available. The housing manufacturers may well say "If you want to take a Canon DSLR underwater choose the 20D or 300D - we already make housings for them. What does the 350D really give you?"
I hope I am wrong. I think that this is a pity because the small size of the 350D makes it very suitable for taking underwater in a small housing. But if you want a cheap Canon DLSR get the 300D. If you want 8MP get the 20D.
3 things might save the 350D. 1) Canon are going to sell loads of them, 2) if the 300D is discontinued soon so this becomes the cheapest Canon DSLR and 3) that the underwater digital SLR market is still maturing, and housing manufacturers want to tie new consumers (switchers from compacts, Nikonoses, Motormarines etc) to their brands.
There is a great image of the 350D and 300D silhouette on this thread:
http://www.wetpixel.com/PNphpBB2-viewtopic...ic-t-7527.phtml
Alex