Just returned from our first run for the million (5 women) and we had a great time! In fact, one of the women I went with said that the "adventure" was such great fun that the miles are really just a "bonus." We had a few stressful moments including missing our Nica flight because our TWA flight was delayed 3 hours, someone mistakenly taking one of our carry-ons in Managua, and having our flight out of Caracas delayed because of a sick pilot (which caused us to miss our flight in Miami). But we met some terrific people, some "very cute" flight attendants, and 7 guys also going for the million (5 of whom had never heard of webflyer or flyertalk -- but they know about it now!)
We're all excited about our next trip to pick up the last 3 airlines in 3 weeks, which we'll do at a more leisurely pace. Thanks for all the great information on this board that allowed us to plan this "adventure."

A side note: The Grupa Taca employees were absolutely incredible - helping us rebook our flights and even suggesting a better connection in San Salvador that allowed us to enjoy a day in Costa Rica. They get an A+ in my book!