Why not printing one and see!
Never use the digital zoom if you want good pictures.
I use a Canon G1 and a D30 both give me good up to 8x10s.
The lens is a very important factor.
If you print at 240ppi like I do you get an 8x10 without interpolation (read Best Print) with 1.920 X 2.400 Pix, this is about 4.6Mpix.
Photoshop does a very good job in upsampling using Bicubic, and you should get good pictures 2 or 3 times bigger using Resample.