or at least relatively so. I did a 20 miler this morning at 15.8mph average on an old Cannondale ('96 I think) with toolkit, frame pump, a quart of water and 20 extra pounds that I *honest* have no idea how it got right there on my gut. Most of my other rides, from 12 mile quickies to 40 mile LSD's are at the same pace or close.
Personally, I'm not worried about speed right now, or more precisely, I'm not doing speed specific work like intervals. I do everything in z1, low z2, with occasional forays into z3 on hills, and make it a point to never get into my big chainring. My first A race is a sprint in mid-June, so I have 6 months to lift weights, lose weight, increase my aerobic base, buy some lighter wheels, optimize my bike fit, improve my bike-handling skills, etc. to build to what I hope will be a 21 mph average over my 12 mile sprint race with legs left to run a 5K. I must confess to a fantasy of being able to maintain 20mph over a 1/2IM course in Sept. 03, but would say that is downright unrealistic for next year.
In short, if you're just starting out, don't worry too much about your speed. I would hazard a guess that the real bike "monsters" out there, those 24-25 mph studs, have been biking for a long time, and probably started out where you and I are now. It takes a while to build the endurance base for things like that.
Good Luck,
Rich