I have two bikes - a 2007 Lemond Carbon frame (17lbs) and a Gunnar Crosshairs Cyclocross bike that's steel (21lbs). The Gunnar is heavier for a couple of reasons including a steel fork.
That said, I'm retiring the Lemond this year because it's got a lot of miles on it and because I've run it into the garage once on top of the car. Since CF sort of accumulates damage and then fails catastrophically, I just sort of figure it's time to deal with it and replace it. Of course, there is also the fact that I really, really want a new bike.....
What I'm doing is buying a new frame from Anderson Custom Bikes - I'm on the list for a new frame delivered next winter in time for riding next spring. It's a steel frame too because I like the ride.
I actually found that I'm faster on the Gunnar than I am on the Lemond just because the fit is so perfect and because it has a more comfortable ride. So that's something.
Now here's the deal on bike weights etc... Just because I'm super anal about this stuff, I've built a spreadsheet of bike weights for the new bike. Yes, it's true that the frame is a bit heavier, but I can *still* bring the weight on this bike in under what it currently is on my Lemond. I don't need it to be lighter than that. What's even neater about it though is that I'm having the bike built so that it can take my current Ultregra mech and then migrate to internal routed electrics in the future.
As far as weights go on the Gunnar, I'm going to have that bike to weighing in at around 18.1lbs when I finish my upgrade project on that bike (Ultegra 6800+carbon fork vs 105+Tiagra crank+steel fork). And it will ride even better, I'm sure.
Basically, the weight comes a third from the frame, a third from the wheels and a third from the components. So any additional weight in the frame is going to be not a showstopper.
What I've found is that you can get a steel frame that is, for all intents and purposes, as high performance as for a carbon frame (for most people). It's not the bike that you would probably choose to race on but it's going to be a plush but high performance ride for the rest of us.
So, being an engineer, I'm sort of always geared to the latest tech. Without researching it, I was pretty biased towards the newer composites etc.. But after building up and riding my cross bike, I've really learned that the new steel bikes are not the steel of old and they are considerably advanced. Richard Schwinn (Gunnar/Waterford CEO) said it best, "If all bicycles were made from aluminum, titanium, and carbon fiber, then someone invented steel, it would be hailed as a 'miracle material." He's right.
For specifics - I'm quite happy with my Gunnar frame and found it to be a good value.