Actually an 8x10 with a 3MP would print at 200dpi, and that's not too bad. It's not the best resolution but it's what many printers do. For a 300dpi you'd need a 6MP picture to print an 8x10 at that density.
The G2 has a 13MP camera, so it's more than capable. However, not everyone takes pictures at that resolution, so it's up to how the phone is configured. If it's anything like the latest Samsung devices with 13MP cameras, you can't go lower than 6 MP.