I'd like to see a full download service. Internet connections are getting faster all the time. when the Xbox 360 was being designed, I was probably still on 56k or maybe had just moved up to 512k. The next gen is probably a couple of years away so by the time It's in its prime, we will probably mostly be on 50/100mb connections. you could say similar with HDDs sizes/prices. It won't be an issue. Anyway, their 'typical' aimed user is only going to buy 5-6 games a year. If an online system was done properly, it could bring many benefits. there's no point restricted a generation of consoles that will probably be released in 2012-2014 and be good untill 2020+ by today's internet connections.
How about being able to download and play any game for 30min for free. After that it becomes locked untill you either buy it or delete it. and how about being able to buy gaming hours rather than the full game or nothing. If a mate at work asked me to play Fifa online with him, I'd have to say no because I'm not interested in football and also because I simply don't own the game. BUT if I had the option of downloading it for free and playing the free trial I would. then say I like it, I could buy 1 gaming hour and play some more. If this went on and I found that I actually enjoyed the game which is possible, I could buy the full game and have my gaming hours refunded back to my online wallet. No loss to them, they have sold a game. There's lots of possible benefits, those are just a couple of examples.
I hope that they wait at least 2 years because, even though they could make a good improvment on the current gen, once you draw the line, that's going to be it for 5+++ years. The current gen is still 'good enough' so it's better to wait a bit longer. And also, each improvment in tech is less important than the last. you will probably never get a SNES/MD -> PS1/saturn jump again. the longer you look back, the bigger the jumps. Also look up the specs of the PS1, PS2 and PS3. They are vastly different in every way. RAM, CPU, Graphics etc. All clockspeeds are increased by many many times. If they were to release a PS4 any time soon, it would probably have a smiliar CPU, maybe with 20% extra clockspeed (I know CS isn't everything) a GPU based on a PC GPU of around GTX 460 performance etc. It wouldn't be a big enough jump for the public. It would make headline news that "PS4 is no better than PS3"