The iDM11 has a boxy design (it looks a little like a miniature version of the) with a corner shaved off so the speaker sits at an angle. It's pretty stylish (I liked the blue light at the base) and feels well-built. This is arguably one of the better-designed products from iHome I've encountered in recent years.
You could put the iDM11 anywhere, but its design lends itself well to a home office, and the inclusion of a built-in microphone means you can use this as a speakerphone like you can the Jambox.
The iDM11 is compatible with all smartphones and devices that are Bluetooth-enabled (A2DP); we had no problem pairing an iPhone 4S with it. As with other Bluetooth speakers, you can range about 30 feet away from the speaker before you start to lose your wireless audio connection. There's a volume control on the speaker, but most people will choose to set that at the highest level--or near it--and control volume from a phone or other portable device.
Sound quality is quite decent for a speaker of this small size, though not great. It doesn't have as much bass as the Jambox and its sound isn't terribly detailed. However, most people should be impressed with its output and that it can play fairly loud. It'll fill a small room or office with sound, but you won't want to crank your tunes to the max because you'll get some distortion at high volumes, especially with bass-heavy music.
I tried a few calls using the speaker as a speakerphone and the sound coming out of the speaker sounded just fine. My test caller said that things on his end sounded decent, though not great (he said that there was a faint hiss and I sounded as if I were calling from outside when I was inside). But, all in all, not bad.