With the exception of the IAH A Gates and Gates B84x, the B Terminal is just fine. Compare what CO is doing RJ terminal-wise with the likes of its competitors (think UA IAD G Terminal, or UA SFO and AA LAX remote bus terminals). IAH B has a Presidents Club, some shops, and jetways for most flights. Yeah it's a bit dated, but that's the only issue.

I'd much rather connect in IAH B to an RJ than say LAX T4 Bus Terminal to an AA Eagle RJ.