Over the past two weeks, I have participated in a couple of HD-quality phone calls, using ZipDX for the connecting service and its version of X-Lite that incorporates the G.722 wideband codec.
ZipDX provides a lot of value-add features for scheduling conference calls, including auto-ID of call-in participants and integration with web-based and other calendar systems. The service is designed to support Polycom’s phones using its trademarked HD Voice technology and also supports (legacy) PSTN dial-ins and dial-back.
Since I’ve been invited in as a participant of a conference, I haven’t had to pay anything; a conference moderator gets billed some amount for minutes and the like; not like the dial-ins are freebies.
There are some other “free” services that support G.722, so I’m going to be poking around and seeing how well they work.