Why might the App Store draw variable-type strings in place of actual values? I have just formatted my drive, and performed a fresh install of Mac OS X Mountain Lion from USB flash drive. When doing my first Software Update, within the App Store application, under the Updates section, the first listed update is the weird looking string "DAHSoftwareUpdate" with title field having the value "DAHSoftwareUpdatesPage.OSUpdates.Title".

Underneath this title, is the correct name of the update (OS X Update Combined 10.8.2, iTunes 11.0.1. Also under the progress bar I see FileSize.MB of FileSize.MB, then the remaining time in minutes.

This seemed odd to me, especially after I get zero google results for "DAHSoftwareUpdate" or even "SoftwareUpdatesPage.OSUpdates.Title".

One possibility, that seems extremely remote, is that the MountainLion.dmg which has been moved around between my backup drives a lot, might have been corrupted, and I'm seeing a weird bug in the AppStore app as a result. It seems much more likely that this is a result of something like a bad localization/language setting, but that would not account for the zero hits for the variable names showing. 

Can someone explain what's going on here?
This issue resolved itself after that single update. 
I did reboot once without updating, and the glitch persisted past that boot, but after the update in question was done and the laptop rebooted, there was no recurrence.

As for the likelihood of a corrupted installer dmg, @KevinChen points out that "there is a lot of checksumming that goes on when you open DMGs and apps, so corruption seems unlikely"