There are changes to Matlab under Mac OS X. In particular, OS X "Lion" requires Matlab R2011A or later. Our group license servers will not be able to upgrade to a license key for R2011A, due to licensing changes from Mathworks.
Instead, users needing R2011A or later will need to point their Matlab to our new license server. We currently have this running on a temporary machine for testing and early deployment, but we need to defer rolling out R2011 to all of ECE until we've had time to build and test our new department-wide server (which will be virtualized, so we need to license and configure VMWare server, etc. as well.)
Current Mac users who want to upgrade to OS X "Lion" will need to contact us about getting R2011A or newer, set up to use the temporary license server.
We're distributing the Mac edition via USB key, as this is much simpler for users than running the installer.
(Editions of Mac OS earlier than "Lion" can still use Matlab R2010B or possibly even earlier, using the existing group license servers.)