What’s surprising is not that Time-Warner has finally decided to file for divorce from its former trophy bride, AOL, but that it’s taken so long to get round to it.

NEW YORK – Time Warner Inc. (NYSE:TWX) today announced that its Board of Directors has authorized management to proceed with plans for the complete legal and structural separation of AOL from Time Warner. Following the proposed transaction, AOL would be an independent, publicly traded company.

Time Warner Chairman and Chief Executive Officer Jeff Bewkes said: “We believe that a separation will be the best outcome for both Time Warner and AOL. The separation will be another critical step in the reshaping of Time Warner that we started at the beginning of last year, enabling us to focus to an even greater degree on our core content businesses. The separation will also provide both companies with greater operational and strategic flexibility. We believe AOL will then have a better opportunity to achieve its full potential as a leading independent Internet company.”

After the proposed separation is complete, AOL will compete as a standalone company – focused on growing its Web brands and services, which currently reach more than 107 million domestic unique visitors a month, as well as its advertising business, which operates the leading online display network that reaches more than 91% of the domestic online audience. AOL will also continue to operate one of the largest Internet access subscription services in the U.S.

Quite so.

In the time-honoured fatuity of corporate PR, the AOL bosses are over the moon about this. AOL Chairman and Chief Executive Officer Tim Armstrong said:

“This will be a great opportunity for AOL, our employees and our partners. Becoming a standalone public company positions AOL to strengthen its core businesses, deliver new and innovative products and services, and enhance our strategic options. We play in a very competitive landscape and will be using our new status to retain and attract top talent. Although we have a tremendous amount of work to do, we have a global brand, a committed team of people, and a passion for the future of the Web.”

Time Warner currently owns 95% of AOL, with Google holding the remaining 5%. The press release says that, as part of a prior arrangement, Time Warner expects to purchase Google’s 5% stake in AOL in the third quarter of 2009. After repurchasing this stake, Time Warner will own 100% of AOL. Accordingly, once the proposed separation is completed, Time Warner shareholders will own all of the outstanding interests in AOL.

Lucky them. Meanwhile, for those with poor memories, Good Morning Silicon Valley points out that AOL, which

was valued at more than $150 billion when it merged with Time Warner in 2001, is back on the market. But this time, despite its reach of “107 million domestic unique visitors a month,” it’s worth considerably less, with an analyst estimating its value at $5 billion.

And before you ask, that $105 billion is not a typo.