Here are some advantages to upgrading to Windows 7 sooner rather than later.
Microsoft's enterprise desktop operating system has a long-term pattern of OS upgrades: Windows 7 is the long-term successor to Windows XP, just as XP was the clear successor to NT 4.0.
Each of these was the golden child of the Microsoft machine, blessed with prime market positioning, lack of extreme overhauls and sporting a high level of polish. As the latest entrant, Windows 7 is here to stay and adoption rates are already very high.
Once you accept that Windows 7 is coming to your environment sometime over the next several years then the question truly becomes: "What are you waiting for?" The sooner that you get Windows 7 in place, the sooner you can make the transition and the sooner you can start reaping the benefits of the latest technologies. Most shops are moving from XP to 7 today.
Migrating to Windows 7 earlier gives your users maximum time to adapt to it and giving you more time to take advantage of its features.
Windows 7 runs nicely on both Vista-era equipment and much of the XP-era equipment and also takes good advantage of new hardware making it a good option for in-place software upgrades.
Having a Windows operating system that actually outperforms its predecessor on the same hardware is a major feat. Traditionally an OS was only expected to be comparable or faster when used on hardware current to its release.
Unlike any other Windows upgrade, Windows 7 can be deployed onto existing hardware without needing hardware upgrades and you will still see small performance gains. This alone removes one of the traditional obstacles to in-place operating system upgrades.
This update makes UAC (the bane of Windows Vista) into the security tool that it was always meant to be. UAC is now easy to use and control but still powerful enough to protect you in critical ways.
Moving from XP to 7 provides a very important security update, while moving from Vista to 7 makes this technology user friendly enough so that it can remain enabled without the bulk of users demanding that it be removed.
Solid state drives work best when the drivers handling them are aware that they are solid state. SSDs should not be treated like traditional, spindle-based hard drives for maximum performance and reliability benefits. Windows 7's solid state enhancements like TRIM and removal of spindle drive tools like Superfetch and ReadyBoost give SSDs better performance and longer lifespan on Windows 7 then on previous Windows iterations.
These features may not seem like a big deal today but over the lifespan of Windows 7 as SSDs become more and more of an expected desktop component for the average office worker these SSD-specific features will play a bigger and bigger role.