Why doesn't Microsoft Windows drop its price over time?

Looks like pricing information and release date has been announced. Intentionally or not, the info's out there. The purchasing price for operating system software, especially those from Microsoft, doesn't seem to decline with time. This is one of those rare technology purchases you can get in on early without having the price cut in half a year late. Jumping on the new OS bandwagon early can be cost effective because your ownership time to the next major release is that much longer when purchased early on. Be warned though, be prepared to download patches like crazy if you are one of those getting it on January 30, 2007. Here's the information from PC World:

According to Amazon.com, Windows Vista Home Basic will cost $199 for a new copy and $100 for an upgrade. Windows Vista Home Premium, a step above Home Basic in functionality, will sell for $239 for a new version and $159 for an upgrade. And Windows Vista Ultimate, the highest-end version of Vista for consumers, will cost $399 for a new copy and $259 for an upgrade, according to Amazon.com. Windows Vista Business will cost $299 for a new copy, while an upgrade will sell for $199.