I commute to work on an e-bike. I love it. There are two kinds of electric bikes, one is called a pedelec, and it means that the electric motor kicks in automatically when you pedal, based on how much effort you put forth. Sometimes a pedelec offers an additional controller for the level of electric assist you want. An e-bike's electric motor is controlled with a throttle, so the rider can set how much electric assist she wants (including none at all).

Python mentioned that electric bikes are often over 88 lbs. For the older models with lead-acid batteries, that's true. However, as battery technology has improved, so has the weight of the bikes. My folding e-bike with battery is 51 lbs. Not exactly light, I realize, but it is not too heavy for me to lift up my front steps to my house. It's part of my workout. Some electric bikes are in the 40-45 lb. range.

My e-bike is rideable on flat ground and downhill with no electric assist at all. On a hill, the electric is wonderful but also needed due to the weight of the bike. One of the roads I ride on to work has minimal, slow-moving traffic and wide lanes, but also several hills. If it weren't for the electric assist, I wouldn't be riding that road, despite its otherwise great arrangement for cycling. I could do it on a "regular" bike, but I would be so burned out that I'd likely ride less often and be less motivated to ride in general. That's just me.

The other thing I love about the e-bike is that it gets me out of intersections and other tough spots very swiftly. Granted, if I were an experienced cyclist, this wouldn't be an issue, but as an occasional recreational cyclist who has recently started commuting by bike, I find this very helpful. When a traffic light turns green I can get up to speed quickly. As I get more fit and experienced, I can use the electric assist less often.

One downside with the electric bike is the higher cost, but a conventional bike can be converted to electric for a few hundred dollars. There is the additional expense of replacement batteries, however. Also, I have to keep my battery charged, but since I have a charger at home and at work, this hasn't been an issue for me. Another downside could be the attention it gets from the general public, but in my experience, most people don't seem to notice I'm riding an electric bike. Schwinn is coming out with a new line of electric bikes next year, and the battery and motor are hidden so well it's hard to tell they are electric. I'm sure other manufacturers will follow Schwinn's lead in terms of design.

Overall, I think electric bikes are fantastic. They're not for everyone, but for those people who want to level out their pedaling effort, improve their fitness gradually, or who can't pedal too much due to health concerns, they may be what you're looking for.