If you've ever dealt with Microsoft's support for both their software suites or Windows, you've probably heard about the term “end of life”, which applies to when a company no longer will support a product at all. Microsoft took an enormous amount of heat just a few short years ago when they had planned to cut Windows 98SE out, and they eventually rescinded that decision, providing support for longer than they had expected. Now, they are overhauling their entire system of product support, implementing a “5-plus-5”, which gives “mainstream” support for 5 years from a product availability date, and an additional 5 years of paid support. Eventually, it will affect all Microsoft products.

”Exchange Server 5.5 is the first product to be affected by today’s change, which will be effective across all Microsoft products, Vargas says.
"As part of our ongoing effort to improve the Microsoft Support Lifecycle program, we’re going to review all of our products over the quarter to make all of those date changes," she says, "and we’re going to implement the new support dates for all of our products."”

This is primarily aimed at businesses making use of their server software, such as Exchange and server versions of Windows. To many businesses, this is good news – they can continue to operate their systems for several more years without the risk of losing support. This can also be a double-edged sword, however, because some businesses may be inclined to not seek upgrades or migrations to newer software. The extra 3 years of support is paid, however.