FYI - As another option (but I've not tried) that you could do away with Tune Blade all together and use one of the iOS / Android based Airplay streamers to push the audio from your phone/tablet to all the Airplay devices (eg the Phone/Tablet becomes the server and player).
I think it depends on what your goals are.
Aside from the fact that there seem to be issues using the Airfoil Speakers app with TuneBlade right now (and I'm in contact with Rogue Amoeba about this) here is how my setup currently works:
TuneBlade is configured to capture from the HiFi Cable audio device (which is configured as a zone in Media Center) and automatically transmits that audio to any AirPlay receivers that it finds.
This way I don't have to do
any management at all to have whole-house audio playing.
If someone brings over an extra AirPlay speaker for a party (as one example) or one of the receivers has to be reset for whatever reason, TuneBlade just automatically finds it and starts sending audio to it.
So the AirPlay zone in Media Center is only used for "whole-house" audio, it requires zero configuration to work, can be controlled 100% through Media Center on a PC or JRemote on a phone, and the audio stream is not reliant on a mobile device.
The AirPlay receivers are connected to other speaker systems, so we just switch them on/off depending on whether we want to hear music in that room, and control volume locally.
I've found that this is the most seamless approach to whole-house audio, since using the TuneBlade/Airfoil apps to switch receivers on/off or control volume makes things more complicated than they need to be.
If I want to play to a specific receiver, I will play audio locally in JRemote on my phone and use it to "forward" that audio to a specific device. (since iOS supports that as a system-wide feature)
Perhaps it's different on Android but on iOS you can only forward audio to a single receiver, not a group of them, so it cannot replace the TuneBlade/Airfoil servers on the PC - not that I would want to, because then you would be reliant on the battery life of the device, and audio is being sent to the phone wirelessly, then forwarded to the receivers. (again, wirelessly)
I can see that with AirPlay-enabled AVRs or AirPlay speakers, this may not be the ideal solution, since those devices may automatically switch inputs or come out of standby, in which case you would have to manually configure your active AirPlay receivers in TuneBlade/Airfoil.
Or I can see situations where you may want to transmit audio from the PC to some of the rooms, but have someone else playing their own music in another room (e.g. the kids have an AirPlay speaker in their bedroom) but having TuneBlade automatically transmit to all receivers it finds hasn't been an issue for me thus far.