I can't speak on non-U.S. products, but I'll give your post a little *bump*.
Haven't managed to get a definitive answer from anyone yet so here is my question again:
I purchased my region 1 Sammy BD-P1600A from a BestBuy in Canada and I just upgraded the firmware to 2.04 after hearing about added MKV support after 2.02.
Everything seems to be operating normally with playing blu rays, but I still can't get the player to see or recognize the .mkv file that I placed in a USB flash drive. The USB is formated to FAT32, and the mkv is AVC not DivX, so I don't know why it is not being found by the player.
So is there anyone with a BD-P1600A that has managed to get a mkv file to play either via USB or DVD?