Soon To Be
Ratchet & Clank Future: Quest for Booty
Ratchet & Clank Future: Quest for Booty is assumed to be the first game in the series to be exclusive to the PSN. It was orginally thought to be downloadable content for Tools of Destruction but may be an entire new game itself due to the recent rating from ESRB. No release date has yet been confirmed but it's predicted that Insomniac/Sony will annouce it at E3.- Wikipedia
The pair's debut downloadable outing, Ratchet & Clank Future: Quest for Booty on the PlayStation 3, received an exact release date today on GameSpot's latest episode of On the Spot. The smaller-than-usual-size game will arrive on the PlayStation Store August 21, complete with a smaller-than-usual-size price tag: $14.99. Picking up after the events of Ratchet & Clank Future, Quest for Booty will put a greater emphasis on puzzle-solving and platforming elements. The game will also incorporate a new light-and-dark gameplay mechanic.
- Gamespot
Ratchet & Clank Future: 2
In an interview with James Stevenson and Brian Hastings, Insomniac confirmed that there would be another Ratchet & Clank Future game.It would be the eighth installment in the series, and would take place after Tools of Destruction. The title has yet to be decided. At the moment, it is Ratchet & Clank Future 2. It is likely to focus on Ratchet trying to track down Clank after the Zoni mysteriously snatched Clank at the end of Tools of Destruction. It will also give more backstory about Max Apogee (mentioned several times in Tools of Destruction), the Lombaxes, and Clank's mysterious snatchers, the Zoni. A probable release date would range from late 2009 to mid 2010.- Wikipedia
Here is a video about Tools of Destruction by the developers with some hints for #2: