The next generation console should be developed after further advances in the technology they utilize. Examples would be TV/visual (better than 1080p) and media formats(thing to succeed Blu-ray).

If you used the Sony Playstation's development as an example:

Playstation: made for CDs

Playstaion 2: made for DVDs

Playstation 3: made for Blu-Ray Discs

Playstaion 4?: made for ????