I am in my mid-40's. Literally. I turn 45 this year. So every year, strength training becomes more and more important. I've really been focusing on strength all winter, and got an excellent functional strength training program from a pro triathlete friend of mine. It's 3x/week, with lots of variety in each session. Jason's been doing it too and agrees about how effective it is. We have a spare bedroom in our house set up with mats, exercise balls, free weights, kettle bells, TRX... pretty much everything we need. Right at home so it makes it easy to prioritize.
I also figure that with the knee injury I have, and therefore am on an enforced reduced running plan (as much as you can reduce the running in Ironman training), the stronger I am the better. So 2015 is the year of strength.