I just got home from the Polyglot Conference (followed by a couple of days of sightseeing in Budapest).
My overall impression was one of being extremely welcome. It was a friendly and supportive atmosphere, with no sense of competitiveness and no language snobbery. If anybody feels a little intimidated by the many highly experienced polyglots at these conferences, then those fears are unfounded and all are welcomed with open arms.
I must confess, it was quite a strange feeling to meet some of the many faces I have seen in videos, and also for many people who had seen some of my videos to greet me like a long-lost friend. It was certainly unexpected, and very pleasant.
In terms of the conference itself: three things were going on.
1: Lots of presentations spread over two days. They were on a variety of topics, so it is hard to generalise. Some were about languages and language learning, whereas others were about using languages as part of your job. I felt it was a good mix. As noted in comments above, the whole conference was videoed, and the videos will be uploaded to youtube within a month. They are certainly worth watching - although it may take a great many hours to watch them all.
2: There were frequent breaks and casual meetings where people inspected each others name tags in search of common languages. I was a little nervous about this at first, but soon found that nobody was under pressure, and again it was all done in a very friendly way.
3: Socialising in the evenings. Apparently, there were large gatherings in pubs and restaurants in the evenings, which by all reports were lots of fun. I was not, alas, able to participate in these since my wife was with me and I promised to spend the evenings on romantic walks and dinners with her. It does seem that most people attended on their own (although there were a few couple there) and I would say this is probably better in order to fully participate after-hours, unless (of course) your partner is equally obsessed with language learning.
Overall, I was hesitant to attend the conference at first, since I was not sure I was “good enough” to mingle with renowned polyglots. I was even more nervous when the organisers asked me to give a presentation. Both worries were unfounded. Nobody treated me as “lesser” than them, despite my inferior polyglot skills, and my presentation was warmly received.
I look forward to the conference next year, and am extremely motivated to work on improving my languages in preparation.