Windows Vista grabbed almost one percent more of the OS market in October, according to figures from Net Applications. Vista represented 19.29 percent of web users, up from 18.33 percent in September. Vista’s share in October 2007 was 7.94 percent.

Windows XP’s share was down, from 68.67 percent in September to 68.11 percent in October. The market share of Mac OSs was mostly unchanged, going from 8.23 to 8.21 percent in October.

November marks the two-year anniversary of Vista’s release to manufacturing; its retail release was in January of 2007, so Vista has had an average growth of around one percent market share per month. If Windows 7 meets its expected release date—a year from now, or a little more—that would put Vista in the 30-35 percent range with steady growth. Even if XP loses share as quickly as Vista gains it, it’ll still be in the area of 50-55 percent at that time.

Of course, all of this speculation is based on rough numbers and assumes past trends will continue, but it’s looking like XP will still be more popular than Vista by the time the next version of the OS rolls out.

Trying to decide whether to move to Vista? Check out 10 Reasons to Deploy Windows Vista  and 10 Reasons Not to Deploy Windows Vista.