Do you think the TF3 toys will be part of this new "Transformers" line? with tf3 Power core combiners and such?
No chance. There will definitely be a new packaging design and new line oriented around the third movie.
Definitely not. The line will most likely end early next year, so that TF3's line can take over. Like RotF, it'll be Transformers "whatever the subtitle is", so that people will instantly associate the products with the new movie. Also, while I think it would be a good idea, I wouldn't expect it to return/continue once TF3's toy line is over. Hopefully a new show will have taken over at that point (I'm still not convinced we'll see a new show before TF3 comes along).
it's way too soon for TF 3! They should wait another year so we can enjoy Generations and the new series. But no! Hollywood needs another franchise installment right away!