Why? Start the Software Update Server within Mac OS X Server and never have to wait for that stupid blue bar. Updates that may have taken 20-30 minutes now take seconds, literally. I've started our software update server with the click of a mouse. Saving bandwidth, time, hassle, and users not doing it because it takes too dang long. I'll let you know some more behind the scenes actions at a later date.
http://www.apple.com/server/macosx/softwareupdateserver.html
You don't have to purchase a new server, you already have this INCLUDED with your server software. Just make sure you have at least 10-20 GB of EXPENDIBLE space available to store the updates. I don't know how much it actually takes, but I wouldn't enable this feature with only 10 GB available on the boot drive. I say EXPENDIBLE to consider normal growth and expansion, especially if this is where you store users' homes.
