I've been looking into PS3 myself lately. Point your PS3 browser to http://www.adobe.com/products/flash/about
and you should see what version of Flash the PS3 browser is using. When I tried this I got version 22.214.171.124.
However, I have noticed some other irregularities. In my case, all my SWF's are generated through flex builder, but it seems that sometimes they are not visible. My first guess is that some wmodes aren't supported, but I'll have to look into it further.
If anyone knows compatibility issues for the PS3 Flash player, then please let me know in this thread!