In 522+, Google Calendar Week View entries for the current day are offset left by a number of pixels as compared with other days and the same page when viewed in Tiger Original Safari/WebKit. See PNG attachment. Offset is persistent and robust - doesn't change if entries or window are resized or redrawn.
Created attachment 13379 [details] 75KB screen shot of image offset bug (Google Calendar Weekly view) Top browser is original Safari, bottom is current WebKit (2007-02-26). Note offset by about ten pixels when 520+ is displaying the same page.
I think this regression started with the non-integer percentages bugfix. As you can see in the screenshot, the difference is not in the positioning of the events, but rather in the layout of the grid behind them. Google calendar uses non-integer percentages for the grid, but adjusts the positions of the events in order to work around the Safari 2.0 bug. Now that the bug is fixed and the gridlines are positioned correctly, the workaround is unnecessary (and harmful).
Per Mitz's Comment #2, this is now an evangelism bug.
<rdar://problem/5721949>
Simon, does this still happen?
No, seems to be fine in Mac Build r39572