Do you realise there's 15 implementations of exercise cycles that connect to a console, PC or the internet? There's some pretty poor implementations, but quailty aside, this is a post of quantity!
Fitness cycles are found in the gym, traditional cycling is used in government health promotion and is never questioned as a cardio workout. There's distinct categories within the 16 products.
1. Speed Mediated Gaming - The faster you pedal the faster your car/cycle/monster truck etc goes on screen. Most products are in this category, and most implementations are for PS2. Due to licencing restrictions, digital next gen bike controllers are limited to home brew versions.
2. Movement Mediated Gaming - Play any game, so long as you are exercising. Stop exercising and the game play is paused. Patented Gamercize interaction products, working with all the next generation consoles and PC.
(via http://exergamelab.blogspot.com/2010/01/get-your-bike-on-exergaming-bike.html )