Anyway, here's what happened: Not to say that big brother is everywhere, but short of having microsoft people monitoring our lists and newsgroups (with wouldn't overly surprise me, after all they also tried a PR compain with magazines, posing as simple users who liked microsoft products), the announcement was available in several places, including freshneat and Linux Today, as well as the Svlug web page, so I did expect some microsoft people to have learned about it, some way or another, and to be waiting for us there.
They were actually much smarter than that, and did what I hadn't quite expected: two microsoft people, Dan Frumin and Mike, met us at the cafe where we had planned to meet before going to the ms event. Basically they were worried to have an unknown number of linux geeks rampaging around their party, and kind of overwhelm the place. Our goal wasn't obviously to ruin their party, but it's true that having 30 to 40 geeky looking people, with our crazy Sam Ockman harassing people in suit with Linux CDs (just kidding Sam ), might have been somewhat disruptive.
Their offer was to give us 5 SVLUG badges to let 5 of us in at a time, and let us rotate. Their claim was that you actually had to have received an invitation from them before being able to RSVP.