Check out
Aoife McEvoy’s review of AIM PhoneLine vs. Skype Beta 2.5.
Some of the challenges that AOL’s phone team faced were likely similar in many ways to similar hurdles that the Yahoo voice team’s is finding in bringing voice into an IM world. The IM clients weren’t architected for voice so voice has to integrated into them. That’s not as easy as it seems and is a contributing factor to this type of review and comparison.
Skype was built from the ground up to do what it does. Gizmo Project was also designed from the ground up to be a voice product as was SightSpeed for video. So in reading the review one has to remember that it’s a far cry easier to add IM to voice or video compared to adding voice to a legacy Instant Messaging application.