switch brands ?

Hello everyone.
As a d300 owner and lover.I am also concerned about being abandoned by Nikon.

I must admit I have researched other cameras I.E Canon 7d especially after recent firmware update,Sony A77,and Pentax K5.
All seem very impressive all reviews are very good on all three.

But I would like to hear some input of actual D300 users who have shot with any of these cameras and their "real world "opinions. Would you switch?which one?and why?

I realize this has been hashed over but I have not seen it in one place and also from d300 user perception.Thanks in advance