UPDATE: Capcom appear to be reconsidering certain elements of their DRM plans, but removing GFWL is not on the table, and they say that removing the DRM completely is "not feasible". They also discuss removing the DRM from legitimate copies of the game in the event of it being cracked.
Here's a new one. The original Street Fighter 4 sold well on the PC by Capcom's own admission, but apparently some folk found a way to acquire it without paying for it, so they didn't bother releasing the PC version of Super Street Fighter 4 that they had already more or less developed. I hope no one tells them that piracy happens on consoles too, or they'll maybe stop releasing any games, and just produce them for their own amusement. They've had a change of heart for the latest iteration though: they'll be letting PC gamers give them their money if they so choose. Super Street Fighter 4: Arcade Edition is coming to PC, and it's learnt a few new DRM tricks too.
As a mechanism to ensure no one will ever be able to pirate it ever, Capcom are locking out features of the game unless you are logged in to GFWL, and online. If you are offline, you will only be able to use 15 of the cast of 39 characters (that's 61.5% of the characters you will be cut off from, percentage fans), you lose the ability to save any progress in the challenge mode, you cannot save any settings, and you will be cut off from any of the (purely cosmetic) DLC that you have bought.
If your internet connection drops, or if their servers are ever unavailable, here's what will happen:
You'll be able to keep doing what you're doing until you come to a logical break point, like exiting to a menu, at which point you'll be asked to sign back in. Assuming your PC is back online, everything will continue as it should, just like on Xbox 360.
If you are not able to get back online, or if their servers remain down, you will be forced to exit without saving, and start again in the restricted offline mode.
GFWL has always had restrictions in place to protect the achievements system, as promoting the Xbox brand is obviously amongst the biggest priorities Microsoft have for GFWL, but restricting access to content that has no bearing on achievements just seems arbitrarily draconian. I understand, even if I don't appreciate, that they feel the need to maintain the integrity of leaderboards and achievements, and GFWL does serve that purpose. However, couldn't they just let people not interested in any of that console guff just opt out of achievements and public leaderboards?
I'm not sure if ensuring that the pirated version has a better offline mode than the official version will help them realise their goal of 0% piracy rate either. For a lot of people this DRM will probably be tolerable (especially as the online SF4 bouts are arguably its major draw), but it's turned me right off. I'm also not too keen on them setting the digital RRP at £30 and the physical RRP at £20 (and some places selling it for as low as £17.86).
On the plus side, it has fairly meagre system requirements, an acceptably long list of graphical options, comprehensive Xbox and not-Xbox controller support, and matchmaking that pairs people up based on the benchmark results (for framerate reasons that I am no way near good enough at fighting games to fully understand).
You can read all the ins and outs on the DRM and all sorts of other details about the PC version over at the Capcom Unity blog. It's worth a read if only to see Capcom apparently encouraging people who live in any of the 160 countries that are unsupported by GFWL to fib about where they live so that they are able to play the game.