Unfortunately Not - really don't understand why they can't add this !
Only way to send to multiple speakers is via the 'remote' application - which is then really using iTunes on your Mac to send the music.
Yeah, the lack of multiple speakers streaming in iOS is lame. though my current set-up works great and doesn't rely on airplay multiple speakers. I have my airport express connected to my both zones of my a/v receiver (if you're interested in how I do this, let me know and I'll give you the details on the multiple zone / digital & analogue set-up for airport express or apple tv). The main zone is the living room where the home theater is. for the second zone of the receiver, I connected a fairly inexpensive wireless speaker system. Each speaker is about $100 and I have three of them in different locations around my house (can have up to 6 connected to a single transmitter with this system and can buy them individually to add on later if I want). I have found this to be a great solution for me the following reasons:
- I only have to stream content from my iOS device or computer to one airplay device which is connected to the a/v receiver (the a/v reciver handles the distribution).
- No syncing issues at all since I'm only streaming to one airplay device.
- Don't have to worry about my wifi range for the zone two speakers - just have to make sure the wireless speaker transmitter is in range of the wireless speakers.
- At $300 for three speakers I own, this is about the same price as the three of the cheapest airplay enabled speaker I could find (philips fidelio) and much cheaper than buying three additional airport expresses and 3 decent non-airplay enabled powered speakers. And WAY cheaper that sonos (not to bash sonos, though - I understand It's pretty awesome). Plus, the speakers I have have a ton of other options, e.g. indoor / outdoor use (water resistant), both the transmitter and the speakers are very portable and can take batteries, can plug a device directly into the speakers which is nice if you wnat to take the speaker on the road, etc., etc.
Anyway, sorry for rambling, but just thought I'd share this insight as I've found it to be a great way to get music all around the house with my iOS device since apple doesn't hasn't given us multiple speaker airplay for iOS.