Wikitravel is very similar - I believe wikivoyage forked from wikitravel some years back, and my understanding is that many of the primary contributors moved to wikivoyage.
I went on an extended backpacking trip recently across 5 continents, and Wikitravel was unbelievably invaluable. Because it's a wiki, it has all the tiny up-to-date details that you're not going to find on more professionally-produced websites, right down to sidestepping tourist rip-offs like "if you go around the corner to XYZ plaza when you land, you can get a taxi for $20 cheaper than taking it from the airport".
For our service, however, it's not necessarily just about finding the "right" counter or "right" service it's having your own personal problem Solver to help you through the airport. If you're a company and you're sending an employee on an international trip for the first time, you want that reassurance that your employee (often your most valuable asset) is safe and comfortable. After all comfortable employees are productive employees.
Back to normal travelers - I wish there were a free wiki that covered all this, since it seems like it's just a matter of having the right information. Like knowing which office to go in, what forms to have ready, etc. I guess it'd be more targeted towards casual travelers who won't pay $200 for this kind of service.