Originally Posted by HarryT
The range of ePub books is still vastly less than that of MobiPocket, although it is very easy to buy in other formats (eg LIT) and convert to Sony's LRF format.
I would, however, second the recommendation for the Gen3 for all the reasons mentioned: mobi format support, dictionary lookup, fonts, and something else which hasn't been mentioned - the fact that it has a user-replaceable battery.
That's a very important fact. Go for the Cybook.