When I first heard about paying for downloads on the PS3 before I got mine on launch day I never thought I would do it. I prefer actually owning my games, which means having a durable, physical copy that is not on a rewritable media. I have had my PS3 for over 2 years now, and guess what? I have paid for 5 downloadable games and 11 SingStar videos!
Why did I do it? First of all they were all reasonably priced for downloads. $1.50 for SingStar videos and all of the games I downloaded except for WipeOut HD were all $4.99 or less. WipeOut HD was $19.99 for a game I would have gladly spent $60 on if it was on Blu-Ray.
Secondly, all of these games are only available as downloads. PSN has some really great downloadable games, but you can only get them as downloads.
The bottom line is if you can release enjoyable downloadable games for a reasonable price, people will buy them. There is no way I would buy a 100% digital distribution console unless the majority of their good games were for $1.99-$19.99.