I took one lab yesterday HOL24 with the Horizon App Manager. It looks like a really great product.
Some info from yesterdays VMware mail.Take note of the last sentence.
Even though the Solutions Exchange closes tonight at 5:30pm, you can stop by and take a Lab until 10:00pm – or- stop by tomorrow morning at 7:00am.
So far 4,900 labs have been with 54,000 VMs deployed, and any attendee who has completed more than 4 labs can now get a Fast Pass which will get you to the front of the line.