There are a number of reports related to Adobe Connect that can be found on the adobe.com site at the following URL:
http://www.adobe.com/solutions/customer-experience/industry-insights.html
The key reports from this page are listed below
Gartner Magic Quadrant for Web Conferencing 2011:
http://www.gartner.com/technology/reprints.do?id=1-188BRJH&ct=111206&st=sb
The Forrester Wave: Web Conferencing Q2 2010:
http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/enterprise/pdfs/wave-web-conferencing-q2-2010.pdf