Well heres to hoping this is true cuz again, from what i've also heard, this game ends on a cliffahnger. they ust finish the story if it does. it has to be canon.
Blackman is a great writer so they should get him back. And so far it looks like TFU2 ends on a cliffhanger. So hopefully here LA will break their tradition of not finishing their trilogies.
I've come across news reports on the web of interviews with Julio Torres, the project lead of the Force Unleashed franchise, stating that TFU3 is not cancelled and that work is currently being done on it. Here are some links to back this up. Also Haden Blackman, now the head of Fearless Studios, is willing to work on the Force Unleashed 3 if Lucas Arts will allow him to do so and he already has a story in mind. This is the third link.