All of this is a long way from how games, and software in general, were handled in days of yore. In the before-time, the long-long-ago, one would go to the store or mail order some disks with the software on it, install it, and that was that. Patches were next to unheard of. After the advent of the internet, one would still likely go to the store and buy a game on discs, and then begin the process of downloading patches off of the internet, if one was so lucky to have their product see post-launch support. Today, it's not uncommon to see a game be patched once or twice in a week's time, especially so if it's a game with an online component to it.
With games like Dota 2, and recently-released Tribes Ascend, and the wildly successful Minecraft before that, the entire software development cycle gets hazy at best. PC Gamer recently asked its readers whether or not they should review Dota 2. There's still a list of things to come for Dota 2. There's also already a selection of purely cosmetic items available for purchase for your heroes, tying in closely to Valve's hat-based strategy for revenue. It's no wonder that reviewers are left wondering. Buyers are wondering too. There are plenty of people playing Dota 2, and presumably some of those players are having fun doing it. I think it could also be successfully argued that Minecraft was "done" long before Mojang slapped a 1.0 version number on it. On the flip side of the coin, it's been five years since Valve released Team Fortress 2, and the TF2 that players play today is very little like the one that was bundled with the Orange Box on release. Games developed, or even merely published by Bethesda are notorious for launch-day bugs, some of which are so egregious that they come perilously close to breaking the "sacred bond of trust between gamer and gaming mega-corporation." Sometimes Bethesda fixed up their games with a post-game patch, other times we have to just wait and bear it, and eventually at some point, like the days of yore, post-launch support just ends, and bugfixes are left to the community to handle.
I think that in the end, the "release early, patch often" approach is beneficial to consumers. It allows developers to get player feedback in an early and ongoing fashion, and adjust their product accordingly. In the long run, it makes it easier to decide whether or not it's worth plunking down our cash for a game. It does, however, make it much more difficult to decide to do so on launch day. It's difficult to see the future and know if and how a given title will be supported post-launch, which is now a reasonable issue to consider before purchasing a AAA title that can cost between $50 and $60. The hard part, of course, is waiting for our old ideas about game reviews to catch up, since a review doesn't get patched, unlike the games they cover. The best a review can hope for is to be revised during an expansion pack.