Google?...no idea. But Wikipedia is assembled by a group of experts in that particular field, Law, the Arts, etc .etc and is added to as time goes on by anybody that has up to date data.
What drives me mad is the links in Body and Soul which are based on people knowing what they are talking about, not what they think they know and many of the links are totally inappropriate.
If you know without doubt, the subject, confirmed by experts in that field, then Wikipedia and Google are invaluable.
For me the main problem is that it is so impersonal and that experience counts for less and less.