Yes, I received one at 10:30 pm local time last night. When I clicked through at 8:30 am LT this morning, I received this message:

Thank you for your interest in participating in this survey.
Unfortunately this survey is now closed for respondents matching your characteristics.

People are still getting in so I guess you have to be careful how you answer their questions or you don't make the cut.

I didn't even get to answer a thing. The front door was closed shut after 10 hours. Dunno why?

Got the email and signed up. Looks interesting.

Its been a week and they have not added any more things to discuss. More people are joining but not much input from AdSense team so far.

Some people are posting their web sites which is kinda interesting to look at :)

Most of the people invited seem to have been using AdSense for years.

Yes, it seems to be a fairly successful bunch. Nice to see.

Received the email late night @ 11:50 PM while i was asleep, by morning 10:00 am it was full.

Thank you for your interest in joining our panel today. We very much appreciate your time. Unfortunately, either our panel is now full or the group for which you qualify has now been filled.

I got the email but didn't realize it was a closed AdSense panel. Thought it was an open forum.

They give out a Nexus tablet once a month and some swag for top posters.

Joined after seeing this post. Yeah it's closed panel by invitation only. Pretty cool.

[adsensepubpanel.com...] is their official link login page.

I joined too, if only to get advanced warning to changes in the program and to voice my opinion. Here's hoping it's actually productive.