The speed that technology changes are absolutely amazing in that as soon as you buy something, the next faster, bigger model comes out. I think back to around when I started my career and remember a workstation that I was using with a 200MHz processor and I was really thrilled when I got it bumped up to 64MB of ram. Now although the hardware was changing at blazing speeds you used to know you had a three to five year run with the operating system before you had to worry about upgrading and refreshing the operating systems. VMware has been changing the rules the last few years on major releases coming around every two years.