Semicolons: it's too bad Netscape didn't choose to use colons instead (but then it wouldn't sorta look like C, would it).
As opposed to common dogma as this is, JavaScript is essentially a line oriented language, like Ruby, Shell Script, BASIC, Groovy or dBASE. OK, so it's more like Ruby, where the line will continue if it doesn't look done.
Had they used colons instead of semicolons, it would have been obvious that "oh, I'm using this punctuation to add another statement to this line", but of course, it's usually the null statement in JavaScript.
It's a shame JavaScript (and Ruby) didn't adopt the line continuation character convention (e.g. - backslash or ampersand) for incomplete lines. As it is, one might be best served by learning what incomplete statements look like, just in case, and alternately, where the parser might think your statement is shorter than you intended.
Yes, I add the semicolons at work to avoid the > contest.