Absolutely I’d pay for BM. I’d have payed for NS2 if they hadn’t abandoned their modding community like they did.
I know I may be overly sensitive about the subject, but ever since Gearbox abandoned the Op4CTF community during the Steam roll-out, I’ve made it a point to suport devs that support their communities.
Case in point: I’ll be buying L4D2, because I believe Valve when they say it has enough content to warrant a new game. On the other hand, I am seriously on the fence about buying Borderlands because while it looks fun, I’m still holding a grudge against Gearbox.