It's tough for companies to upgrade to a new OS like this. Not only do they have to pay for the OS (which could cost millions depending on the size of the company), they also have to worry about hardware upgrades (in a company like the one where I worked last summer where every single one of its 18,000 employees has one to two computers, that could cost a shitload), AND worry about software not being compatible.

For example, I believe IE6 is unsupported by Windows 7 (and should be). The company I worked for had a system produced by Oracle for ordering parts (there were millions of parts so a good database was needed and this database was fantastic), keeping track of what is in stock, finding out what needs to be ordered, etc. that was only compatible with IE6. I tried it on IE7 and it didn't work one bit. It worked in Fx 2 but I couldn't use certain necessary features so it was essentially crippled.

Doesn't surprise me. The company I'm and intern for is just NOW upgrading to Vista. And even then very slowly... mainly because it's still causing them numerous issues. For example, there's only one set of print drivers compatible with Windows Server 2008 (I think it is), Vista, and XP. Oh, and best part? It doesn't support 3/4 of the features the employees are used to, such as automatic stapling. So, yeah, it's an insane fail and I predict that's the same reason for this.