If Microsoft issues all 12 of the security patches it has scheduled for release on Tuesday, including some that it skipped on its last "Patch Tuesday", it could equal its record for the number of patches issued in a month. 

Several of these patches are listed by the company as "critical", Microsoft's top security rating.
At the time of going to press, the patches listed on Microsoft's site include five for Windows (critical); two for MS Office (critical); one for Windows and Visual Studio (important); one for Windows and Office (important); one for Step-by-Step Interactive Training (important); one for Data Access Components (critical); and one for Windows Live OneCare, Defender, Antigen and Forefront (critical).
This, of course, could change. January's Patch Tuesday saw only four of a scheduled eight patches being released.
Microsoft's record of 12 patches in a month was set in two separate Patch Tuesdays last year.