Patch 5.1 ends that. Not only can Razorgore be soloed (in theory), but a couple of other older dungeon bosses have been tweaked just a little.
Having checked a couple bosses out myself, I can say that while they appear noticably easier, you shouldn't get too cocky. Razorgore's Destroy Egg cooldown, for example, is down to 1.5 seconds, but there are still a lot of eggs to bring down. If you aren't careful, either you or he will probably be beaten down by all the adds before you can get them all down. Really, I'm kind of rooting for another nerf (perhaps to the number of eggs or adds) before the patch goes live.
Still, anything that makes it easier to get at those sweet weapons off the later bosses (and the cool new battle pets they drop) is fine with me. Bring on patch 5.1.
Mists of Pandaria is here! The level cap has been raised to 90, many players have returned to Azeroth, and pet battles are taking the world by storm. Keep an eye out for all of the latest news, and check out our comprehensive guide to Mists of Pandaria for everything you'll ever need to know.