This plan is mostly from the book Run Less, Run Faster (the FIRST plan). When I got my marathon PR in Huntsville in 2007, I did it after using a very similar plan that had me running 3 days a week. I really think my body operates best when I run 3 days as opposed to 4 or 5. That's just me.
I altered a few things from the plan in the book. Mostly, there were things that I knew from my previous four training cycles that didn't suit me... so I changed them to something I knew would work better.
Of course, I won't be following the first 2 weeks quite as closely as I'd like since I'll be in EUROPE! I will definitely get the two long runs in, but the other runs will be substituted with a TON of walking. I'll pick up with week 3 when I get home and hopefully won't find that missing those four workouts will hurt me.
I'm also going to make a point to try to get to one spin class a week, one yoga class a week (or pilates), and do some strength training once a week.
Oh... you're not misreading. I'm running a half-marathon 8 days before the marathon. Don't freak out. My training plan called for 10 miles at marathon pace on that day. That day is also the day of one of my favorite half-marathons that I have run every year they've had it. I don't feel like I can miss it. So, I will MAKE myself use the first 3 miles as a very gentle and easy warm-up before I run the last 10 miles at race pace like the plan called for. I'll probably cut a couple of miles somewhere along the way those last 2 weeks as well.
So there you have it... this will be a big part of my life for the next four months. I can already tell it's going to be worth it.