8.0 vs. 7.4 benchmarks

Hi all!
Has anyone done any performance benchmarking of postgresql 7.4 vs 8.0?
Are there any scenarios where 8.0 can be expected to be faster? I
would love to get my hands on any numbers that someone might have.
Also does anyone know how long it will take for a stable release of
8.0 to come? Given the loads of additional features in 8.0, I can't
wait to use it in production. :-)

thanks a lot everyone!!!
ps