Often not compelled to write a review, but this fantastic speaker is really so good, I wanted to share my experience with it.
I was looking for a single 'box' speaker that was unobtrusive, and I could move from kitchen table to bathroom, patio etc.
I spent some time looking (and trying) Tivoli Pal, Tivoli Model One, lower end iPod docks and even a PicoIR internet radio.
But all I wanted was a *speaker* - I have radio etc via my iPhone - the sound was lovely (esp. Tivoli), but I felt like I was paying for a feature I don't need.
And then I remembered this Jambox device; I'd written it off as gimmicky when it was released. Shows what i know, huh? :)
This has the same audio performance as a Tivoli, I reckon- a nice, warm sound, which definitely benefits from decent quality AAC/source files - you notice the difference with iPlayer's 'HD' and 320k iTunes material.
The audio is noticeably 'box bound' (depending on the track), but as it's the size of *two Wii remotes* - it's an amazing audio performance for it's size.
If this was simply a mains-powered, smallish speaker, with audio-in, as I thought I wanted, I'd be really happy.
But of course, this also has a 10hr battery and bluetooth connectivity (and a headphone-in if you need it), so I can carry it from room to room, with my iPhone (or Mac) left behind (30 feet range - I've not reached that limit yet).
I didn't think I needed this sort of portability, but it's absolutely brilliant - you really do find yourself using it whilst cooking, showering, etc.
I didn't think I'd need a speaker to carry around my flat, away from the phone/mac, but it's really useful.
And it looks pretty cool! It's like a nifty piece of lego...not some horrid nerdy hifi object with flashing blue LEDs. It feels extremely rugged as well; thick rubber on both sides and a meaty metal grille.
**UPDATE**: I've been using this for a week now, and the battery is outstanding - I've charged it once, and used it for: afternoon's loud listening, a movie, an evening's background music, an afternoon's listening, morning's radio. Still reporting 'about 3/4 full', and the iPhone's battery indicator (v. cool) looks about 2/3rds.
It's been a week, and no run-down on the battery whilst idle, either. Absolutely fantastic.
It's also a doddle to pair by holding the power switch for a few seconds - I haven't tried more than two devices (iPhone and Mac), but it shows up as a source in every audio-enabled iPhone app I've tried so far.
One thing I was concerned about was the syncing of audio for video playback (I was previously unfamiliar Bluetooth audio), but it's perfect.
Because it's battery+wireless, this has transformed how I watch movies on my laptop (I place the speaker near my head, and the laptop at the bottom of the bed :)
Some thoughtful extras in the box are two lengths of micro USB cable (the shorter one is great for travelling), and a lovely thin headphone-heaphone cable (I suspect audio nerds will detect improved quality sound with this - I couldn't hear much difference over Bluetooth).
But best of all is a really nicely designed 'slipcase', with toughened sides, so you can carry it in a bag.
Note for Mac users
Word of warning to Mac users - it shows up twice in Sound preferences - the default source is 'headset' and that is really rubbish and tinny. Be sure to select 'Bluetooth Headphones'.
**UPDATE**: I've had some problems connecting my Mac over Bluetooth (iPhone is flawless). I think the Mac has a Bluetooth bug which requires you to wait for 15+ seconds to connect successfully. If you try and access System Preferences > Audio in the first 15+ secs, before the device driver has become active, the Sound prefs hang, or you get a 'can't connect' error.
As the iPhone is flawless, and instant, I'm going to put this down to buggy/sub par BT audio drivers on 10.6.7...I'll just have to learn to be a little patient when using my Macbook :-)
It's not full-on hifi, but you've probably already got a dock/stereo/whatever for that.
This is basically a near-perfect kitchen table speaker for connecting an iPhone/laptop.
Then it becomes one of the best travel accessories I've come across - the battery and size (and weight) means it'll slip easily into an overnight bag (it comes with a nice slipcase...never suffer hotel room audio again!
If you like well designed, thoughful objects, like good sound, but are willing to compromise a bit for wonderful portability and lots of opportunities to actually use the thing, I don't think you'll regret buying this.