Hi Marc,
Thanks for posting! Yes, NCrunch will need to support MSTest's async tests. This will be done with some additional work to bring NCrunch up to speed with VS11 in the long term. Likely this will be done without the 'vstest.console.exe' though - as NCrunch requires greater control over the test environment.
I'm glad your enjoying NCrunch :)
Cheers,
Remco