It is out on March 12 and I have been using it for two weeks at home.
I found that although it is still in beta version, it is pretty stable and I could not see obvious difference between 3.0 and 3.5 when I first time use it.
Summaries: All the good stuffs have improved its performance and added some good new stuffs in it. I am very happy to use it because it is really better than current version. Don’t take my words , just install it and find out yourself, I bet you won’t be disappoint. I can not wait to see the final version of Firefox 3.5, hope it won’t delay again.