If you're connecting in PHL because you fly USAirways, I'd choose CLT for a winter connection if I had the choice. PHL is accustomed to snow and are equipped for it, but preparation and such can only do so much. It's in a congested northeast corridor and when weather gets ugly, things get ugly. For novelty sake, PHL is a fine airport but I'd choose it when there's a lower chance of snow in a coin flip with CLT. The hour is fine for any connection without delays; obviously MSP to PHL has 2 winter airports so you're doubly at risk.

I would either fully check bags or carry on; gate checking would be bad. Gate checking through F would put me outside my comfort zone at 1 hour -- I'm not sure if US files any pencil jets to MSP, but they generally end up at F and MCP is likely to be an A320/319 from B or C terminal. Airside connection, but requires a shuttle, so doing that plus waiting for gate checked bags (frequent on pencil jets) would be uncomfortable for me.