Many companies are forsaking Windows 7 and sticking with Windows XP; some are just starting to plan for Windows 7, but are in no rush; some are in the process of deploying Windows 7; One company, Baker Tilly, a UK accounting firm, is that rare customer that has pulled the trigger and completely deployed Windows 7.In an interview on Microsoft's Windows for Your Business blog, Baker Tilly's IT Director Simon Harding-Rolls discusses the decision to upgrade now.Windows 7 Bible: Your Complete Guide to the Next Version of WindowsSome of the key points from a chat with one of the world's earliest Windows 7 adopters: Baker Tilly was using Windows XP on all its computers, but realized they had squeezed all the business benefit it could out of XP. After evaluating the Windows 7 beta, the firm began testing Windows 7 in its environment and found it to be compatible with most of its applications and deliver better performance.The firm has deployed Windows 7 to 2,318 seats over about 30 sites and completed deployment on July 17. Baker Tilly is running the Enterprise Edition of Windows 7 RC (release candidate) and plans to deploy the final version of Windows 7 during November at the same time it is rolling out Windows Server 2008 R2. The deployment took four weeks, with all the work done outside of normal business hours.Baker Tilly started application testing in February, developing test builds, and then deploying them to the IT department for formal testing and also to the appropriate users within the different departments of the firm. There were some issues with the Windows 7 deployment, particularly with the early builds. Functionality misbehaving and app incompatibility were the standouts, but all were resolved with assistance from Dell (A Baker Tilly partner) and Microsoft, as well as improvements in more recent builds of Windows 7. In conjunction with Windows Server 2008 R2 planned for November, Baker Tilly will be deploying networking and security features DirectAccess, BitLocker and Branch Cache to improve performance and flexibility for its users. IT Director Harding-Rolls says that every company's needs and resources will be different, but that if you do deploy Windows 7, "plan, develop, test, test again and don't take steps that are too big \u2014 its just like climbing Everest really!" Click here to read the complete interview with Baker Tilly's IT Director Simon Harding-Rolls on the Windows for your Business blog. Are you a Tweeter? Follow me on Twitter at twitter.com\/smoneill. Follow everything from CIO.com on Twitter at twitter.com\/CIOonline.