You might think that but my experience shows different. Most users spend over 90% of the time learning the new menu system. In 1 hour, you can take care of over 75% of their concerns. The other 25% is about allowing them to simply interact and try the new OS themselves.
There's 2 areas of focus, the first is the end user portion which is the easy part, done it for over 500,000 clients, many of them not what you would consider computer-savvy. They were able to learn XP to 7 without much issue, most of the concerns I had to address was the new Control Panel icons, Personalization and new features unique to 7 (like how to put 2 windows side-by-side on the same monitor by using WIN + LEFT/RIGHT arrow hotkeys, etc.) As far as using IE/Firefox, the icons looks pretty much the same as before, using Outlook (on Exchange) is no different, they use the same apps as they did before (Excel, Word, Powerpoint, etc.).
Then there's the guys who support all the users, this is the big challenge. You can't simply print out a document and expect know all of the changes from XP to 7 in a timely manner. It's much more time-efficient to send a few of your staff to class and get them updated on the new changes, then send them to update their certs. End users don't need to know the changes made to the network stacks in Windows 7 from XP, but the support team does.
Businesses stay on XP for their own unique reasons, cost versus need to upgrade. Not all machines currently running XP will be able to take advantage of Windows7 without replacing their current with new computers. I don't expect a shop selling comic books and baseball cards to rush out to change out their XP system to 7 for example... but a bank, school institution, city and county/state systems on the other hand...
I hope that clarifies a few things.