We've been using a new (to us) meeting tool that we really like: http:/fuzemeeting.com .   We have used Glance, DimDim, GotoMeeting, Yugma and a couple of others too.  Here are some things we really like about FuzeMeeting:

No client-side software download: Essential and clients can upload content for viewing too.  You only need the software download to share your desktop.

HD Content: You upload presentations or documents and they convert to beautiful HD content.  Much nicer than screen sharing a PPT presentation. You also keep a content library, making it easy to bank things for later meetings.

Desktop Sharing:  Works as expected, and easy to switch back and forth between sharing your screen (say for the browser) and the presentation.

HD Audio: The conference bridge audio is great. The chat window is nice too.

Nice UI and pretty easy on price too, with a free account option and reasonable pricing tiers. Highly recommended by the Socialarc testing team!