i just bought a 40 gb mp3 player, and am currently filling it up with cds. so i'm not sure of the answer, but i do know that it holds at least 25.
actually, i was also concerned with the size of the memory, if it would be enough. i asked my friend who has a 40 gb ipod, and he said that he has about 300 cds on his, and it's only about 15 gb of memory, which means it should be able to hold around 800, give or take a few depending on the length of the album and the size of the files such.
[quote name='rockhero']I have 385 albums ripped and they fit find on my 40 GB iPod.[/quote]
but how much space is still available?