It would be nice if it were possible for WordPress to automatically adjust the UTC offset for daylight saving time.
Currently, one has to adjust this value manually as soon as the time switch occurs or risk having inaccurate publish times. (This is actually quite problematic for my blog, which has a strict posting schedule.)
I understand it's prohibitively complicated for WordPress to keep preset options for every possible region on the planet, but a set of conditions such as "second Sunday in March to the first Sunday in November" could be used. Or, at the very least, include the option only for the most popular regions.