The generous streak at Time Warner's (NYSE:TWX) AOL keeps rolling on. Following the February announcement of its new corporate IM service, the company announced that the business-focused service will be free of charge. Is AOL on the offensive or the defensive here? Either way, it's got its work cut out for it.

Last month, both AOL and Yahoo! (NASDAQ:YHOO) discussed plans to open their IM clients to developers in order to offer jazzier applications for chatty Internet users. In a surprising turn of events, given AOL Instant Messenger's longtime lead, recent comScore data suggested that AIM might be losing ground to rival IM services. Meanwhile, Yahoo! and Microsoft's (NASDAQ:MSFT) MSN Messenger have called a truce, allowing their users to talk to one another at long last. That's surely a trouble spot for AIM, which still keeps its users and their buddies walled away from friends using other services. (There's lots of buzz about when and if AIM will allow its chat client to operate with others.)

AIM Pro, codeveloped with WebEx (NASDAQ:WEBX), features a customized interface, conferencing and other collaborative tools, enhanced security, and screen names created from business email addresses. Other interesting features include an enhanced Buddy List, with headlines from The Wall Street Journal and other services, as well as the ability to access podcasts from various news providers. There's also a People Search function, allowing users to search for information on professionals from a database of 31 million business profiles and two million companies.

The press release I received from AOL calls the notable lack of price tag for the service a way to "super-serve business users." This marks an interesting shift in strategy -- or perhaps the ultimate refusal to switch strategies, since the consumer-oriented AIM has always been free.

When I wrote about the initial AIM Pro announcement in February, AOL didn't have pricing details finalized, but it seemed to be leaning towards a subscription-based, per-user fee model. Whether or not corporate users would want to shell out for tricked-out IM has always been a question; as I pointed out at the time, all the major IM clients have begun to integrating bells and whistles like videoconferencing and voice in their free products. The shift from fee to free may not be quite as interesting as AOL's possible plans to eliminate fees for most AOL members, but it's pretty darn close.

IM continues to be a popular way for folks to interact with one another, whether it's through text, voice, or even video. Of course, the competition is heated; even Google (NASDAQ:GOOG) wants in on the action. Its Google Talk client hasn't gained much traction, but one can only imagine Big Goo has plans up its sleeve. AOL's seeming migration to free products and services is interesting, emphasizing its continued challenges in wooing -- and retaining -- the online audience it once dominated.

Time Warner is a Motley Fool Stock Advisor selection. To find out what other companies David and Tom Gardner have recommended to subscribers, click here for a 30-day free trial.

Microsoft is an Inside Value recommendation.

Alyce Lomax does not own shares of any of the companies mentioned.