But to get there, the hurdles have been, and will be, great, he said. "Weve overcome numerous technical, business and detailed user experience [feedback] to make it a reality," he said. But when asked whether that years-long effort has included talks with AOL, Irving declined to comment.The pressure this will put on AOL is obvious.AOL recruits blogging and social networking companies to improve its IM presence on the Web. Click here to read more. During a teleconference, Irving and Dan Rosensweig, chief operating officer at Yahoo, downplayed how popular AOL is, saying that outside of the United States, its popularity tapers off. The Radicati Group Inc. has reported that Yahoo and Microsoft will now command upward of 44 percent of the market. Other research from comScore Media Metrix backs up Microsoft and Yahoos claims that the integration will give the two companies the largest IM community globally, with a combined MSN Messenger and Yahoo Messenger reaching 33.5 million unique users each month, compared with 23 million AIM users. AOL had no immediate comment. When asked whether the integration will encompass outbound calling, Irving and Rosensweig said that both companies are making sure that VOIP (Voice over IP) is integrated as an "integral point of the relationship." "Thats a priority in the immediate term," Irving said. Voice will be restricted to PC-to-PC connections, however, Rosensweig said. Additional IM features, like making phone calls or text messaging to a cell or landline phone, arent a focus for the short term. "We just want to get the basics right," he said. Thats a blow to telephone companies that provide a bridge between the IM windows and traditional phones or cell phones. For now, they are left out of the financial opportunity of the largest-ever community of potential Internet telephone users. For instance, IM users can, and some do, pay a few pennies a minute to make calls from their IM window to cell phone or traditional home phones. To enable that, IM makers hire companies such as Level 3 Communications, a major communications network operator, to connect the calls. A Level 3 representative had no immediate comment. Check out eWEEK.coms for more on IM and other collaboration technologies.