According to rumors and a Tweet from CNet's Brian Tong, Apple is set to launch their new Mac Pro, and Mac Mini in early August 2011.  The fall release is set to feature upgraded CPU with Sandy Bridge and Thuderbolt along with the newest OS X Lion. 

Tong's Twitter posting states:

EXCLUSIVE: My sources tell me ALL NEW Next-Gen Mac Pros and Mac Minis will launch either end of July first week of August, tweeted Tong. 

In a later posting, Tong wrote that a likely date for release could be August and suggests that buyers wait for the new machines to hit the market. 

If the release dates are true, Apple will have an impressive line up of releases from now until the end of the year with their recent iCloud, OS X Lion along with upcoming launches of the Macbook Air, iPhone 5, iTouch, and iPad 3 (scheduled for 2012).