Sega back in console... Touchy subject for many gamers. My only true concern is that they wouldn't have enough popular first-party titles, but enough skirting around the question.
1. Low, LOW price point - Anywhere between $250 to $100. Sega's new console would not and should not have to be all that. They should first produce a decent console to gain back the trust of fans, but nobody would buy something from a company that hasn't made a console in years for over $250.
2. Online service - Doesn't have to be the best, but should be free. I'm not paying to play Space Marines or whatever games Sega makes now online.
3. Motion control - Yeah, I realize we are leaving that generation, but it is still a somewhat modern technology and going tablet like the Wii U would nullify point 1.
4. More first party games! - Sega, get some good franchises. Buy Crash Bandicoot or something, dying franchises that contain fans that you can do justice to! I was just on their website, they are currently advertising Total War Shogun, Yakuza, Binary Domain, Renegade Ops, Captain America, etc. ... I WOULDN'T BUY ANY OF THESE!!!
5. Sonic Adventure 3 - Fan dream... Deal with it.