There has been a lot of movement in the autos space as entrepreneurs drool over the high advertising demand and see the obvious flaws in dated sites like Yahoo Autos. See, for example, recent social networks that have launnched such as Boompa and Motortopia.
Wikicars is notable because of the solid resources behind them with Internet Brands, as well as their choice of MediaWiki as the wiki platform, which is the core technology behind Wikipedia and Wikia. WikiCars is allowing use of its content via a liberal creative commons license as well.
If done right, WikiCars will be a deep, and neutral, public resource for car information. To start things off, they’ve made a real effort to properly build out the hybrid car area of the wiki.