Today AOL launched a new product, AIM Pro, that takes the AIM protocol and merges it with the WebEx business suite. With AIM Pro, AOL is taking advantage of the fact that many businesses use some form of instant messaging to communicate. The new product is advertisement-free, features encrypted conversations as well as Outlook integration and audio/video conferencing capabilities.
I think the strongest draw for companies will be the out of the box integration and encryption. At Yahoo! we all use Y! Instant Messenger (obviously) and I'm a little paranoid at times since it's unencrypted and traffic is monitored/logged.