Unfortunately for players who just can't get enough leveling, the cap is staying put for now -- the team likes it right where it is. However, they also recognize how popular it is to move a new character to max level and then start rolling up alts, and are looking into ways to make doing so more rewarding. They also want to buff out mid-range content a bit, with possibilities of something in the 20-30 range.
Adventure packs, the first of which is due out in June, will help expand the content by being repeatable and runnable by any hero above Level 11. Champions Online players might not be hitting Level 70 any time soon, but it looks like they'll have plenty to make up for it.