TechARP has been spot on for past service pack releases, so their latest report is at least worth paying attention to. The suggested schedule would fit with the timetable Microsoft used for the two desktop operating systems prior to Windows 7. It issued Windows XP SP1 about 10 months after the initial release in October 2001, and delivered Vista SP1 roughly a year after its troubled January 2007 retail debut.
Microsoft claims Windows 7 is already seeing stellar sales, but it might see a further boost following the first service pack release as many businesses usually wait until a new operating system is mature enough before migrating to it. No specific SP1 features were mentioned on TechARP's report other than saying it would fix "a few serious bugs" that could affect performance in certain scenarios.