TripAdvisor is comprehensive and an excellent resource for hotel information, which has two major shortcomings:
1. As some have noted before, it is mostly helpful regarding hotels, and less so when it comes to tips or travel guides. For those I would recommend googling specific locations, or consulting forums. A general tip: get on local sites, and use Google Translate; you won't believe the amounts of unbiased information you can get there.
2. The site is more informative and doesn't allow enough space or volume for complaint. Granted, it is not an anti-fraud site like this one, but the reason most people get on it in the first place is to make sure their hotel won't be terrible or they won't get ripped off by it, etc. So when someone has a dreadful experience with a hotel, their review gets lost in the sea of other reviews (many of which are completely useless and "vanilla" - if you have nothing to say, don't say anything!). That's why the size of the site is a pro and a con.