The Daily Grind: What's the difference between an MMO trial and F2P?

Back in olden times when I sampled my first MMO trial, free game try-outs were short affairs. You'd usually get to play for a week, and then you were done unless you subscribed (or forgot to strike your credit card info). But modern MMOs are abandoning time-limited trials with increasing frequency. Games like Warhammer Online, World of Warcraft, RIFT, and now Star Wars: The Old Republic all allow gamers to play indefinitely -- but only up to a certain level.

The "endless trial" model has led to some debate among the Massively staffers as we try to suss out what, exactly, sets an endless trial apart from any other F2P game and how we ought to refer to these sorts of titles on the whole. It'd be easy to say the restricted level cap is the red flag, but if we latch on to that definition, then any free-to-play title with a level cap locked behind a paid expansion -- like Lord of the Rings Online -- could itself be deemed an endless trial, albeit one with a very high (but not max) level cap for free players.

Chime in on our debate. What do you think represents the key difference between an MMO that's F2P and an MMO that merely features an endless trial? Is it level caps or content or something else entirely? Or is there not really any difference at all?

Every morning, the Massively bloggers probe the minds of their readers with deep, thought-provoking questions about that most serious of topics: massively online gaming. We crave your opinions, so grab your caffeinated beverage of choice and chime in on today's Daily Grind!