Ok, try downloading a copy of Opera Mini and see how that handles CBF. The likelihood is that it's one of the third party applications embedded in the forum pages that's causing the prob.
If you're comfortable with flashing ROM's then email me and I'll send you a link to a slightly more efficient (and well tested) version of WM6.1. I've upgraded a few HTC handsets and both browsing AND battery life have been much improved by using a non-standard ROM.
JF