I have officially completed four half-marathons for 2010, Mercer Island, Washington, Vancouver, Canada, Gig Harbor, Washington Trail Run and the Seattle, Washington all where very different and each had required some planning during the races.
Mercer Island was very hilly and a bit wet. The first six miles went well. I ran with a friend who set the pace much faster than I usually run. We ran 9:00 min miles. The second half of the course was very hilly with a large hill at mile 10. This almost killed me. My quads were screaming. Not the first time to have such pain while running, hence Portland Marathon. I plowed up the hill with three miles left but the legs were hurting bad. We arrived at the last mile and it was very slow. We headed towards the finish with zero extra kick for me. i was tired. However we did make it under 2 hr. 1hr 58min. for my first official half-marathon.
Vancouver half-marathon was much better than Mercer Island. Flat with a large hill at mile 7 and rain. I ran with the pace bunnies who were set to run 2hrs. Feeling good I ran with them the entire way. Learned that the pacer run 10 minutes and walk 1 minute. I had heard of this but never tried it. I must say I am hooked, my legs and body had zero aches and I was able to finish very happy. The pacer I ran with was set to cross the finish at 1hr 58 min, I crossed at 1hr 55 min. New PR.
Gig Harbor. This was interesting as the race was all trail and fire road. I ran this with a friend (Luke) and the race was set to be 12 miles with multiple loops in the shape of a large figure eight. Felt pretty good throughout but started to tire around miles 9-11. Running off road is so much different than the sidewalks or asphalt that I am used to. The weather was perfect and the scenery was pleasant. I finished the race in 2hrs 10min. Slower than I would have liked but OK. Found out that the race was actually a full 13miles not 12miles, as we were originally told. I would try this again next year.
Seattle. The Seattle Half was cold and crowded right out of the gate. I had a variety of issues on this run. Training dropped off for five weeks, my watch was not set correctly for pacing, 
my running partner was nowhere to be found, felt like a sardine running for the first six miles and then came the hills
….ouch. I was at least four to six minutes behind my goal. But the lack of training really showed. I wish I had more energy but maybe next time. I crossed at 2hr 7 minutes for the full thirteen. Not a great race.