I've killed memory, audio, and USB ports with static, but the dry cold weather isn't exactly something that everyone experiences. If you didn't feel a shock when touching the board, should be no problem. Felt/saw the sock, chances are slim, really, but if you touched something sensitive, then maybe. Nearly every board on the market today has ESD protection built into USB ports, and if you do have enough static to kill something, just that port, or set of ports will stop working when fuse is blown. Most boards released in the past 18 months have per-port protection, so you only lose that specific port.