I do 85 miles a week at an absolute minimum. Then again, I commute 5 days a week, and it's 8.5 miles each way!
I usually do another 50 or so on top of that... I can easily get between 15-25 miles a week in various errands, more if I have time to go out on an actual ride on the weekends. Last week I think I did about 150 miles. I went out Sunday afternoon, intending to do a very short ride to just stretch my legs a bit... 45 miles, and two emergency bike assists later (me assisting others with their bikes) I rolled back up to my apartment.
I'm coming off a knee injury, only been back on the bike for about 2 months, after more than 6 months of no riding at all. I hope to get in a lot more miles by the end of summer, maybe some touring!