I also do not lose connection to battle net, it shows me as online to friends, and I still receive any messages they have sent me. It simply pops up the box in game and boots me to char screen.
My computer DOES NOT lose connection from the internet randomly, nor does any device I have running in my house...
EDIT::: If a blue decides to read this post by some small miracle, I've already done the "fix" for rubberbanding involving disabling the offload options (which worked brilliantly btw), and that was months ago. This is a NEW problem.