• Windows 7 Wallpapers
• Vista Wallpapers
• Windows Wallpapers

The Malaysian website TechARP has a pretty good track record with this sort of prediction, and my sources tell me that schedule sounds about right.

Meanwhile, here in the U.S.A., some people are inferring more Vista doom and gloom from this schedule. My buddy Dwight Silverman at the Houston Chronicle says “SP2 is being rushed out the door” to keep up Vista’s momentum. Eweek’s Channel Insider calls SP2 a “last-ditch attempt to drum up sales for [the] beleaguered [Vista] operating system.” The Register says “Microsoft seems to be in a hurry with this release.”

They all need to dust off their Windows history books to see that the reality is exactly the opposite. If Vista SP2 does make its official appearance in April, it will mark a return to normal development and release cycles for Microsoft, which lost its way badly with Windows XP.

I’ve got the proof, in easy-to-read chart format. Here’s a timeline of every Windows service pack Microsoft has delivered since the release of Windows NT 4.0 in July 1996. Each color-coded bar represents the number of days between each service pack and its predecessor (RTM, in the case of SP1 releases). See any patterns?

As measured by service pack releases, the XP era was a distinct anomaly for Microsoft. Over the past 12 years, Microsoft has delivered 14 Windows service packs. The gap between SP1 and SP2 was a record 697 days, nearly two full years. But that pales in comparison to the gap between SP2 and SP3, which was nearly four years. If we throw out SP3 and also disregard NT4 SP2, which appeared a mere 59 days after its predecessor, we discover that the average gap between service-pack releases is around 300 days, or just under a year apart. If Vista SP2 arrives in mid-April 2009, it will be 355 days since its predecessor, or very close to the historical averages.

In fact, the chart gets even more interesting if you include major updates delivered in formats other than service packs. The expanded chart below paints an interesting picture.