Re: Which WordPress and bbPress version combination?
> Can I use the latest production/stable releases of WordPress (2.
> and bbPress (0.9.0.5) together?
You can if you use something to make the cookies compatible:
Those were using bbPress 0.9.0.4 and WordPress 2.7, and there has been some additional talk about adding a line to (or was it removing a line from??) your bb-config.php to make the 0.9.0.* cookies work with WordPress 2.8:
> Is that the best combination?
Best is up to you to decide. I think you will find you can integrate logins and also have the greatest number of bbPress plugins available with 0.9.0.5.
> Will most of the plug-ins or extensions for bbPress be available with those versions?
The majority of the plugins were designed to work for 0.9 and below. There are significant changes to the 1.0 RC that some plugin authors are not updating their plugins until 1.0 becomes finalized.