For those wait-until-the-last-minute-shoppers types out there. If you don't have your arms around which computers have been updated to deal with the early DST, then you might want to run a quick report in ZENworks Asset Management to find out.
ZENworks Asset Management collects and reports Windows hotfix data and custom reports can be used to show you a list of machines that do (or, more importantly, do not) have the published Microsoft patches (see KB 931836 and 928388) to correct this.
To generate a report of Windows machines that do not have one of these DST hotfixes installed, you can use the "dependent report" function, whereby you create a custom report (A) to show all machines that have a particular attribute value and then another custom report (B) that includes orkstation "not in Report" (A) in the criteria.
Of course, if you have ZENworks Patch Management, you should not have to worry about any of this at this late hour.