Just back from the London International Music Show - two huge rooms of the same stuff you've seen everywhere before. The only new synth I noticed was the snoresome Juno Stage (big ugly muzak keyboard) and... well, that was it from the big companies, apart from the Korg Nano range of tiny little USB MIDI controllers. They were at the show but not plugged into anything. They are incredibly small, light and flimsy. Fortunately, they're also absurdly cheap. Even at just £49, the NanoKey is certainly the lamest - obviously built using clicky, rattly laptop keyboard technology. From the way it feels, it seems unlikely to have much velocity sensivity. You might be better off with something like this £50 Miditech Control 25, unless you're really stuck for space. At £59, the NanoPad is worth considering. The pads are a reasonable size, and the touchpad (from the PadKontrol) will be fun. The £59 NanoKontrol looks great, with a good number of knobs, buttons and sliders, useful (if rubbery) transport controls.
It's hard to overstate how cheap and plasticky these things are. The faders are tiny and toy-like, the cases would need to be taped down to stop them moving across the table. The Kaosscilators on the next stand felt sturdy and chunky by comparison, and they will certainly not survive the Mackie Mixbusters. BUT at £60, the price seems right. The NanoKontrol undercuts anything in the market - as Peter says, the closest comparison is the Novation Nocturn, a weird DJ-oriented thing. It's probably more sturdy, but does much less. To sum up: try to see them in the flesh rather than just ordering them online, but if you're prepared for something tiny, cheap and plastic, they could be perfect...
UPDATE: More pictures from the London Show over at Guitar Blog.