We should (hopefully) get the 50mm variant. And yes, I WILL use it in the AT role until we get the BK37's for the Stuka. There are times I use the 9T in the AT role (not in a good while though), with a decent amount of success (T-34's are tricky, but not immune to it). And something tells me the BK5 in the 410 will be a little better than the 37mm in the 9T.
As for bomber/town killer, I can't really say. 110 tails seem a LITTLE fragile against the auto ack (its fragile regardless). I think the 410's tail is tougher (and tougher in general?) so will probably replace the 110 in the town busting role, until eny stops the 410. What you might see, if the 410 is indeed tougher but has weaker guns/ords, is a 110/410 mix, with the 410's going on ahead to deack and the 110's following behind to do all the grunt work. Not likely but I can hope.
For bomber intercept, excluding rockets, it will probably fall on what gun packages we get on the 410.
Sure hope we get that BK5.