New large Drupal site - v7?

Hi,

We're going to start work on a large Drupal site later in the year. Would you recommend we start with v7, so that our site has a longer life before needing redeveloping, or is v7 sufficiently unstable / a long way away from being released that it might make our lives much harder?

Secondly - I've had a look at the v7 code, and I'm surprised to see that you don't distinguish between READ and WRITE database operations. This makes it slightly harder to use Drupal on an existing multiserver MySQL replication platform. I've seen the slides at http://www.slideshare.net/KrisBuytaert/drupal-mysql-cluster/ show why MySQL cluster might not be suited to large Drupal sites, so I'm wondering how people are using Drupal on multiple servers.

Finally, this may not have been the right place to post this question, so if there are more developer-centric forums, please can someone let me know, and I'll wander over there.

Cheers,

rtsh