Technically, the primary lane of all socket 1155 boards could be updated to PCI-E 3.0, seeing as the bandwidth comes from the CPU and the slot is physically the same from 2.0 to 3.0.
Though, I'd be more tempted to go for a Gen 3 touted PCI-E 3.0 supported board. Although PCI-E 3.0 will only kick in once Ivy is in the socket.
I wouldn't consider it foolish to get a PCI-E 2.0 board from Intel's 1155, as it has the capacity for PCI-E 3.0, but I'd be more likely to just go, as mentioned, for a gen 3 board.