A letter from the President on GuildWars2.com announces Guild Wars 2 is now free for everyone, as they hope to show introduce more players to their MMORPG before the upcoming release of the Heart of Thorns expansion. ArenaNet president Mike O’Brien also announces raids are coming to the game, and this article has more details on how that will work. They also offer this post with further details on making the core game for free, their business model going forward, and restrictions they are placing on free accounts, with an "exhaustive" FAQ to cover the fine details. Here's a trailer highlighting the just-revealed October 23rd release date for Heart of Thorns, here's a play for free trailer, and here's a bit on the news, explaining how this does not make Guild Wars 2 a typical free-to-play game:

Guild Wars 2 has the simplest of business models: buy the game and play it as long as you want with no monthly fees. We’ve been championing this as a great business model for MMOs since launching the first Guild Wars® a decade ago. We continue to believe in buy-to-play. It’s good for gamers and good for developers.

This business model has been fantastic for Guild Wars 2 and our fans. Since launching three years ago—almost to the day, today—we’ve sold more than 5 million copies of the game. And we’ve delivered more than 40 major content releases, with world-changing events, Living World episodes, and feature packs, all free of charge.

Expansions are the one place where the buy-to-play model gets a little tricky. When you’re coming in as a new player to a game that has a bunch of expansions, what exactly should you buy in order to play with your friends? The base game and also every single expansion? We’ve seen examples in the industry where that kind of thing has gotten out of control. It doesn’t seem right, and we want to do better. As we get ready to ship our first expansion for Guild Wars 2, we want to ensure that we keep the business model friendly and simple. So let’s be clear that when we say Guild Wars 2 is buy-to-play, we’re only asking you to buy one thing: the current release, Guild Wars 2: Heart of Thorns.

To accomplish that, we’ve already included the core game as a free bundle for anyone who buys Guild Wars 2: Heart of Thorns. And today we’ll go a step further: we’re making the core game free for everyone. For anyone who’s been curious about Guild Wars 2, now you can just go to guildwars2.com, download the game, and start playing.

If anyone can play Guild Wars 2 for free now, does that mean we’re switching business models to free-to-play? Are we going to be one of those games that aggressively monetizes free players through microtransactions? Absolutely not. Guild Wars 2 remains the same game it always has been. We’re making the core game experience free because we’re confident that anyone who loves Guild Wars 2 will buy Guild Wars 2: Heart of Thorns.