Not sure if this helps everyone but on 2011 SOA says the following:
Beginning with the 2011 model year we are producing our WRX turbo engines with synthetic oil and is required for all oil changes. As stated in the Warranty & Maintenance Booklet on page 29, the oil change interval for the WRX is 7500 miles or 7.5 months, whichever comes first. If you operate your WRX under "severe" conditions (pg 30) you may need to change the oil more frequently.
The new 2011 W & M Booklet no longer has the comment in NOTES on page 30...."All turbo charged vehicles are considered to be operated under severe driving conditions."
Just an update. I'm sure not harm in changing sooner than 7500 - after the first 1000 break in - especially if hard driving but looks like synthetic is the way to stay.