Tools menu -> clear private data or ctrl+shift+del

its working quite well but if you want to use extensions you'lll have to wait for final ... most do work but some do not work (completely) I also found some instabilities where the browser does not react for half a minute then goes on finally they included a useful error page by default but I don't see any reason that I cannot wait for 1.5 final

Asa Dotzler - "10 months and over 5,000 bugs squashed"