I saw a fellow runner post a note recently that they were on pace to meet their 500 mi goal in 2011 with 125 or so mi in the first quarter. I wasn't sure where I stood, so I decided to look.
That's 175 miles, on pace for 700 miles this year.
Considering that I ended up with 592mi all of last year, and 603 in my first year of running, that's quite a change.
I don't know if I will get there, and not sure that I want to run that much, but the 50-60mi/month seems like a good pace for me now.