Smannesman: I kind of get it, it's not just a matchmaking service anymore.
But Blizzard Tech is an awful name.
I kind of liked the Battlenet name personally and not sure what their internal logic is for the change. I can only speculate that perhaps they've decided that they want to expand what they do beyond selling their own games and become more like Steam or something, and that they felt they needed to rebrand for that or something. Hard to say for sure, but if it's just to continue as business as usual for Blizzard, I can't see what changing the name really buys them.
Having said that, a name change can be a good thing too depending on various factors - but I agree... "Blizzard Tech" just sounds like a terrible name to me. "Bliztech" would have sounded better perhaps, but who's to say... :)