I know you’re going to hate hearing this, but I’m sure you’re used to it by now: that’s how it worked on vBulletin. :)
I personally don’t think of bolding as shouting. That’s reserved for ALL CAPS TYPING. But when a post gets added to a thread, I like that fact being immediately visible. Bold face does that just fine. I’m open to indicating that with colors – colors that actually look different – but let’s hear from some other folks first.
-Tom