Vista's overall share slipped from 14% to 13.35% during the recent sequential period, which equates to 14.66% among Windows users -- much lower than its all-time high of 20.35%. Windows 7 gained about 1.25% on-month, moving from 15.85% to 17.10%, or 19% of all Windows systems. Microsoft's OS share as a whole has fallen by nearly 1% over the last nine months, but it's not clear what platform has benefited from Redmond's loss.
StatCounter, another research firm, puts XP at 53.99%, Vista at 16.59%, and Windows 7 supposedly holds 22.04% of the total market. That breaks down to 58%, 18%, and 24% of all Windows computers. ConveivablyTech notes that while the numbers may be different between outfits, the overall trend is similar: Windows 7 is chipping away at XP and Vista.