I'll pray for you

I was talking to Derek the other night about that common phrase. "I'll pray for you", how often we say it and just go on with life never giving another thought to the issue of which we told the person we'd be praying for them. One day it hit me, how many times have I told someone I'd pray for them, and then never done it? I wasnt lieing, at the time I had full intention of praying for their issue, but life gets in the way and I would just forget. The Lord began to show me how Ive done this so many times and how my words need to hold more value then I was giving them. Its so important to the person asking for prayer that people are actually praying for them, so why do we (sometimes) give so little thought to speaking that phrase and then never giving their prayer request another thought??
I *mostly lurk* on some yahoo loops and other forums and daily there are threads asking for prayer on issues. Ive gotten in the habit now of not even opening the thread and reading it if I dont have full intention of stopping what Im doing right at that moment and taking the time to present my prayers before the Lord on behalf of that person. Its so nice knowing that I am not reading their prayer request in vain without any intention of praying for them. When the saints cry out to God it changes things. Our prayers are so powerful and we so often just loosly say "I'll pray for you" with no intentions of doing it.
So I guess I ask....how often do you tell someone you'll pray for them and then forget to present the request before the Lord on behalf of that person?