My experience w/ Consumer grade firewalls is that most lack any IPv6
support at all for example CISCO/Linksys.  Check Point/Sofaware's
safe@home series of appliances has no support for IPv6. Apple has IPv6
support in the Airport Extreme's, but the implementation is
troublesome.

Modern client operating systems (Vista, Win7, Linux, OS X) are more
ready for IPv6 than consumer grade edge equipment.

-Mike