This is probably a bit late to be of much use, but I'll post anyway.
A month and a half ago or so I bought a Giro Encore 2 snowboarding helmet. It's one of the few snowboarding helmets that are also certified for bicycling. I wanted something that would play more nicely with my ski goggles and would remove the need to wear a separate warm head/ear covering.
I'd say it works pretty well. There's a bit of a cut-out on the back, so the helmet doesn't dig into my neck (I'm riding a Kona Dr. Dew, not a bike with drops). It's heavier than my regular bike helmet, but that's to be expected. It's not uncomfortably heavy. The built-in ear pads are nice, since it means I don't have to wear a warm cap under the helmet. The strap on the back to hold ski goggles is pretty generic and works fine with my Scott goggles. Also, the chin strap is padded/insulated, which is nice when I'm not wearing a face mask that covers my neck.
The biggest disadvantage is that my head sweats some, particularly if I'm working hard and not cooling well enough through the rest of my body. I'm generally going inside right after stopping, so it's not a big deal, but it's something to be aware of.
Overall, I'd say it's well worth the $60 I paid for it.