The New York Times may be about to start charging people for online access to their articles, using a system in which readers can sample a few free articles before being required to subscribe. Apparently, they’re hoping that their bad experience with Times Select, the previous attempt to put some articles behind a pay wall that flopped (even according to some of their own columnists), won’t be duplicated with this new system.

The decision to go paid is monumental for the Times, and culminates a yearlong debate that grew contentious, people close to the talks say. In favor of a paid model were Keller and managing editor Jill Abramson. Nisenholtz and former deputy managing editor Jon Landman, who was until recently in charge of nytimes.com, advocated for a free site.

The argument for remaining free was based on the belief that nytimes.com is growing into an English-language global newspaper of record, with a vast audience — 20 million unique readers — that, Nisenholtz and others believed, would prove lucrative as web advertising matured. (The nytimes.com homepage, for example, has sold out on numerous occasions in the past year.) As other papers failed to survive the massive migration to the web, the Times would be the last man standing and emerge with even more readers. Going paid would capture more circulation revenue, but risk losing significant traffic and with it ad dollars. At an investor conference this fall, Nisenholtz alluded to this tension: “At the end of the day, if we don’t get this right, a lot of money falls out of the system.”

But with the painful declines in advertising brought on by last year’s financial crisis, the argument pushed by Keller and others — that online advertising might never grow big enough to sustain the paper’s high-cost, ambitious journalism — gained more weight. The view was that the Times needed to make the leap to some form of paid content and it needed to do it now. The trick would be to build a source of real revenue through online subscriptions while still being able to sell significant online advertising. The appeal of the metered model is that it charges high-volume readers while allowing casual browsers to sample articles for free, thus preserving some of the Times’ online reach.