Please add a delay option for location alerts, i.e. make it possible to trigger an alert e.g. 10 minutes after I've arrived at (or left) a location (provided I'm still there at that time, in the "arrived" case).
Often, one will have to do something unrelated immediately after arriving somewhere (for example walk to one's desk, hang the coat, log in, check the mail, etc), so if the alert occurs when one crosses the threshold, it will be forgotten by the time one would be able to do it. On the other hand, it might not be feasible to specify an exact time for this, if one doesn't know one's schedule exactly beforehand.