I have the new 15.4" early 2011 MacBook Pro. It is CTO and it works with Second Life minimally. It is a higher end version of the new notebook with AMD Radeon HD 6750M (1024 MB) plus Intel graphics 3000. 8 GB memory, 7200 RPM HD. I have a late 2009 iMac purchased a year ago and that DOES work with Second Life with much better graphics (defaults to high). The MBP defaults to Low Graphics. If I set it to High or Ultra, the movement is very choppy.
Initially, SL didn't work at all on the MBP, because i used Migration Assistant and it may have picked up the settings of my iMac. Still for nearly $3000, SL should run exceptionally well. Is it SL's fault???