RALINK RT3572 supported in 9.1-RELEASE ?

[Ronald F. Guilmette]

I have a Trendnet TEW-684UB wireless dual-band USB adapter.  Googling
around for awhile leads me to believe that this probably contains an
Ralink RT3572 chipset.

Further googling also leads me to believe that a version of the
run(4) driver which should support this chipset was comitted some
considerable time ago.

Can anyone confirm either or both of these two impressions?  Does
the TEW-684UB contain an Ralink RT3572?  Is support for that chipset
present in 9.1-RELEASE?

If the answer to both of the above is "yes", then where might I find
a "HOW TO" sort of doc which might help me to get this running?  I've
already added the following lines to /boot/loader.conf and rebooted:

           if_run_load="YES"
           runfw_load="YES"

but apparently to no avail.

After adding the above two lines to loader.conf and rebooting, shouldn't
the device thenceforth appear in the output of "ifconfig -a" ?  (Mine does
not.)