Unless I am missing something here, most, if not all, of the higher models of all the common brands have multi-zone functionality. I have 2 AVRs that do this: JVC and NAD. Both of these accomplish this in different ways.
The JVC offers both speaker terminals, and Pre Amp outs, for Zone 2. The speaker terminals are powered internally by borrwoing 2 of the 7 internal amps, which is a neat idea, but comes with a long list of configuation do's and don'ts. I use this AVR in the family room for TV use, and the Zone 2 powers the patio speakers. I ended up purchasing a small 2 channel amp for Zone 2. This works well, but the JVC has some quircks (software bugs?) .
The NAD offers only PreAmp outs for Zone 2. However, because the NAD has both pre amp ins and outs for all 7 amps, I simply routed the Zone 2 pre-amp outs to 2 of the 7 internal amps that I am not using, then use the corresponding speaker terminals to power the Zone 2 speakers. I have combined this with the B speakers to allow for powering 3 different rooms, from 2 different sources. In this set up, the main room is the HT, Zone 2 is the workout room, and the 3rd room is the party room. Additionally, I use the Monitor out S-Video to supply a video feed to the TV in the work out room, so the DVD and Cable Box can also be viewed in the workwout room. There are many limitations to this set up, but it meets my needs.
Both receivers require that I turn on the Zone 2 feature, and select a source. The NAD supplies a 2nd remote for Zone 2 only, while the JVC has a Zone 1, Zone 2 switch on the remote. I am not sure, but I believe that both AVRs will only play analog sources in Zone 2.