Return to Sender?

Series 4s biggest news to date is the presence of companions Rose, Martha and Donna at various stages throughout the run.

So do we really need Captain Jack and Sarah Jane?

In the old days this many characters would appear only in a regeneration vision... So is this the end of Doctor number Ten?

Sandwiching Jack into Last of the Time Lords wasn't really a winner - so how are 5 characters going to work? And what about Mickey??

I am worried by this. However as with Torchwood Series 2 I await the highlights - Martha and the Sontarans (good name for a musical combo!) - with keenness.