[QUOTE=Selective69;1227989]<edit delete> After all, what would stop a provider from creating a screen name and giving herself a wonderful review as to attact business.[/QUOTE]Each of these sites monitor the ip address of the provider and that of the reviewer. Inconsistencies in reports coming from a providers own ip address will get them banned from the site. While this is not fool proof, there is at least some checks and balances to eliminate self reporting or reviews.
Besides, as you said, reason to be skeptical of any single review, especially if you are not familiar with the reviewer. Multiple reviews by known hobbyists is the only way to draw any conclusion in advance of an appt.