My intrepid spotter Ellen Magenheim wrote me a couple of weeks ago:
I noticed this morning in the Times that the headline above the story about Jeremy Lin’s latest performance was “Lin Tops Himself” and it briefly took my breath away since my mind went first to the British meaning (i.e., commit suicide) rather than the American meaning. As I thought about it, I wondered if the International Herald Tribune had a different headline–which it did–and then went back to the digital version of the NYT to find that it didn’t have the “Tops Himself” version either. Do you think none of this variation means anything or do you think maybe it dawned on someone about the unfortunate transatlantic ambiguity?
Sure enough, the article she was referring to–about a New York Knicks basketball player who for a time was a U.S. sporting sensation–had in the online N.Y. Times the headline “Lin Puts Knicks Back on Track.” At the very bottom of the article, in small gray print, are these words:
A version of this article appeared in print on February 20, 2012, on page D1 of the New York edition with the headline: Lin Tops Himself.
Often articles will have different headlines in print and online versions. But it’s amusing to think of some subeditor noting the unfortunate double meaning and stopping the presses to change it. I don’t suppose we’ll ever know. Unless, of course, the New York Times sports desk reads Not One-Off Britishisms and wouldn’t mind filling us in!
notoneoffbritishisms.com 
You say, “Often articles will have different headlines in print and online versions.” Given my own experience, I would have said, “Frequently…,” but it’s all the same, and it frustrates me no end when trying to find the online version of an article I read in print that I want to share via an online link.
See Lynne Murphy’s February 26 post on this in her blog, Separated by a Common language.
Online stories need SEO headlines! Purely factual. And they have to fit a different space.
OK, but how did “tops himself” come to mean “kills himself”?
Glad to oblige. One OED definition for “top” says: “Orig., to put to death by hanging; perh. originally to behead; cf. topsman n. Now usu. simply, to kill (someone); chiefly refl., to commit suicide. slang.” The first citation meaning commit suicide is from 1958: “He also took my tie and belt so that I could not top myself.”
Top used in Britlish to refer to the head. Top-knot = tuft of hair on the head; also sometimes refers to the hair on the head generally.
The headline in Britlish, to avoid ambiguity, would have been: Lin Tops His Performance.
No one has pointed out the American gay usage of “top” as a verb meaning to enter another person sexually, and as a noun meaning the partner doing the topping. In this context, “Lin Tops Himself” conjures Möbius-like images.
I’ve never heard of the gay use of the word ‘top’ – I wonder whether it comes from the older word ‘tup’. It means the same thing and you’ll find it in Shakespeare (Othello Act 1 Sc 1 “but he / Is tupping your white ewe”). It’s still used now in sheep farming and a ram is often called a tup. I think the period when the ram is in with the ewes is called the tup or the tupping.