I've long held that Wikipedia provides a "good enough" source of facts for a lot of information. Sure I wouldn't base my moon landing equations on equations copied from Wikipedia's page on celestial navigation. Not at least until I'd verified the cited facts with "reputable" sites. The trouble with checking other links is it's hard to know if they are reputable as well.
However on the odd occasion I've spotted a fact that looked out of place I consult the history and see if there is much edit warring going on. Also some articles are essentially the work of a select group of people who may not be totally objective. It would be cool if you could visualise that sort of information.