After getting some advice on the board, I just had my clipless pedals installed yesterday. I opted for the LBS rather than cheaper online prices, and I'm glad I did. They really took quite a bit of time making sure I got the right fit in the shoes and the cleats were installed properly and in the right position.
After getting the bike home, I took it for a couple of spins around the block. I'd never used clipless pedals before, so I practiced a bit before taking off. I was worried about getting my feet out of them, but I actually found it was harder to clip in than clip out. Anyone else have this experience? Oh well, I'm sure I'll get used to it over time.
Since I ride quite a bit on busy streets and plenty of traffic lights, I opted for Shimano M324 pedals that are SPD on one side and regular platform on the other, along with some Specialized Taho shoes. After just a brief ride, I could already feel the difference going uphill when clipped in. Can't wait to try them out on a longer ride this weekend.