Now that all the pieces of the puzzle are starting to connect with each other, some pretty cool mashups can be built. Here is one courtesy of Eric Ly from Presdo, based on an idea originally suggested by one of our friends at Google: an Agenda Heat Map, showing the popularity of sessions based on actual user scheduling. As attendees to the Office 2.0 Conference are adding sessions to their Google Calendar, Presdo is fetching the data (anonymously), and feeding it to a Google Spreadsheet, which cells' colors are based on the number of attendees scheduled to attend any particular session. It's interesting to see that out of 400 attendees who received an account on Google Apps on Monday, more than 50 were already using it by Tuesday. We wil publish a revised heat map later tonight. In the meantime, sessions having less than 10 scheduled attendees should really start pimping themselves through blog posts on the conference's website...