Choosing between stable and development snapshot releases for a new high trafficked site After some research, I am planning to start the migration of a high trafficked site from Pressflow 6 to Drupal 7, as the current implementation (Pressflow 6 + 200 modules) is making it crawl. I've read that most of Pressflow 6 (if not all) performance changes have made into Drupal 7, and that's awesome. I will be starting the project in a day or 2 and I was wondering if I should be starting with the stable version (Jan 5, 2011) or the latest development snapshot.  

There is a gap of over 3 months, and I am wondering if I will lose on fixes that made into the 7.x branch in these 3 months (that's a long time for a open source project so popular) and if a new stable release is around the corner. 

I would also like to understand the impact on frequency of code updates on drupal core ( in case I use dev snapshot) and ways to manage it properly.
It's a difficult question to answer, because the status of a release (dev, beta, RC) is not necessarily a measure of it's stability, but rather an indication how well it has been tested before the maintainer released it. A module's dev version can (but does not need to be) more stable than the latest beta, RC or stable release.

IMHO, 200 is a huge amount of modules. If it's an option, consider reducing the number of modules. Often, 80% of a site's functionality is created with 20% of the modules, so the question is if the last 20% of functionality justifies the other 80% of modules.