210,
According to the FCC's FAQ's on this issue units that work in the 698 - 806 MHz bandwith range will be as of 12 June 2010 be banned. Apparently, some people and organizations will receive a notice from the FCC or as they say a 'public safety organization' 60 days prior to the deadline stating the cessation of using such gear. After receiving such a notice if you run afoul of said agencies, you won't be able to say 'I didn't know.'
So it would seem that long as your wireless set works in 697 or less range you'll be fine. Now if you live and work in large metropolitan areas, I think you'll run a greater risk of getting into trouble. In smaller cities, rural and wild areas most likely a lot less to none. However, it just seems the lesser hassle is to dredge up the cash to either get wired mics or invest in new wireless gear in the unrestricted bandwidth.
The so called 'rationale' for all of this is the bandwidths that used to be reserved for analog broadcasting no longer being needed due to the transition to digital signals. The bandwith all of our soon to be illegal gear works in the range that will be allocated for law enforcement and other emergency services. So now in 'trying to keep us safe' there's going to be tons of perfectly good electronic gear dumped in land fills despite the FCC's pleas to 'recycle'. Either way you're going to catch it in the wallet and eventually in the backside.