I've found many Bromeliads to be a lot more winter hardy than might be expected. I have several clumps of Bilbergia and others in my garden that don't have much protection other than overhanging oak branches or evergreen vines. It was no problem this warm winter (20s F for a few hours on two nights), but even in the 2009/2010 exceptionably cold winters (low 20s F for sustained periods for up to 2 weeks), my Bromeliads came through fine with little protection. Even if the plant freezes back to the ground, it will generally rejuvenate from the root crown.
I've also found, by happenstance, the best planting spot for bromeliads. I had some large old Live Oaks taken down several years ago. They had dead branches that were threatening to fall through the roof of our house. I had the tree surgeons leave all the wood from the Live Oaks. Some portions of the trunk were about 3 ft in diameter and couldn't be moved. As they began to decay, I started sticking bromeliads into whatever portions of the bark that I could. The old oak trunks are now just about completely covered with Bromeliads! The oak continues to decay, so I suppose I will need to come up with some more oak tree trunks at some point in the future. The decaying oak also makes great dark, humusy soil once the earthworms and other soil critters have digested it.
Jeremy