While i was attending CHI 2008 there was also a Microsoft booth, as premium sponsors of the conference.
No, the table was not there, but there was crew from the Surface team. Some talks, lot of listening and rumors around the corner, i had new insights on where is Surface heading.

A slimmer Surface
First, the form factor. Everyone wants a slimmer touch-enabled surface, it can be done with capacitive sensing (didn’t you know that it already exists from the french Stantum?) but renouncing some computer vision-related features, like the domino-tag recognition for object detection, that is now a core feature in the first AT&T installation.
Microsoft is really looking at retail, and retail is about things first, so they will not be going the capacivite way (even if they claim a capacitive Surface was already in development), and will stick with a vision-based setup trying to make it thinner.
How? Multi camera setups are the answer, but what about the display, will they switch to LCD or OLED? It will be an engineering challenge for sure, but they really want to move away from the crowd of fridge-shaped multitouch tables out there.

SDK and APIs
We asked for APIs and SDK availability, as researchers, and they were very interested: “yes, we really do want you scientists to play with the thing”.
Unfortunately for now the key concept is “business first”. A first wave of commercial partners, then hopefully the research labs.
They said Surface needs the contribute of the scientific community, as well as skilled user interface developers, so the question is not if they will release the SDK, but when.

IP and patents
Regarding IP and patents, they turned it down, “you cannot patent touching a table” even if someone else is trying to do that.
They said that there will be research papers about Surface internals, and they are deciding what to share and what to keep. So, and i always thought this way, the multi-touch world is more about who “does it right” with some clever algorithms/engineering rather than patenting the whole thing. That said, i think, there will be a lot of patents on underlying hw-related technology.

XBox into Surface!?
And here is the really interesting thing: XBox.
Yes, a possible future for Surface is being an extended XBox, in which you can plug both a normal lcd/plasma display (or projector) with usual gaming gear and also use the surface as as an additional control panel. Think about command and conquer games. This will happen when Surface will shift from commercial-oriented partners to end-user market, and is not behind the corner, but it’s a really feasible microsoft-style scenario, they love the gamers community and know they have the bucks and the potential to create the wave.