Expressing a personal opinion based on experience shouldn't be seen as libel.
For example, I was in an expensive hotel in Paris last week and I fully intend to blog about the bad service I got.
However it would not be acceptable for someone to make unfound accusations etc., or personal attacks.
Common sense should prevail.
This site has attracted one legal letter to date - which isn't bad going
There have been several requests for edits / deletions of posts and I've dealt with each one as fairly as possible.