Ok, here's what I found out after spending about 30 minutes with an Epson Support Tech. Let me know if this sounds right to you (everyone in the thread).
To make a long story short, the Epson's max resolution for playing .avi files is 640x480. While I was on the phone with tech support, I recorded a short video on the G9 at it's 640x480 resolution setting, copied it to the P3000 and it worked. So, it sounds like the P3000 will never be able to play any avi files with resolution greater than 640x480, however, it will of course download them for later transfer to computer.
Does that sound right?
On another note, I tried transferring an avi file I downloaded from the internet at 640x480 but it wouldn't play. The P3000 said it didn't have the right codec.