Guys... a few facts....
1. The PR1.2 RC-leaked, ( so far) is better than any other N900 firmware I've used.... PERIOD!
2. It's source is unknown (it obviously started out from Nokia but it's path to those Chinese servers is not known ) and may therefore contain malware etc. Simply means those using it need to bear that in mind and be cautious. .....regularly check to see what it's up to etc.

Just be aware of the risks.