You know my first reaction was HELL YEAH! Ratchet and Clank is one of the greatest platforming titles EVER
But the more I think about it the more it doesn't seem necessary. There's already been SO many games in the series and the 3rd one so far on the PS3 alone (4th if you count Quest for Booty) is set to release this fall. I really think that franchise has hit oversaturization point a bit and that after All 4 One they should give the franchise a rest for 3 years or so.