Finished them all weeks ago. I enjoy the dailies, especially since as a DPS if I queue for a dungeon or raid then I usually have to wait around a half hour before I get in anyway (I don't play during peak hours) and so I can actually get something done--and earn quite a bit of money--rather than just sitting on a mount in a city. Looking forward to the new ones coming in 5.1, actually.
I do find it interesting that some people say it took them upwards of 4 hours to complete them all each day. Either you're not playing your class correctly or you should try doing them in groups if you're having trouble finding spawns during peak hours. When I was doing the most dailies per day (Golden Lotus, Shado-Pan, August Celestials, Tillers, Anglers and Klaxxi all at once, the others I had already completed) it took me at most an hour and a half. Within a week you should already know the best routes to take and methods to use to maximize your completion rate versus time spent. Where is August Celestials sending you today? Any other dailies along the way? Can you hearth and port back closer to the next set faster than you can fly? Etc. etc..
And of course I don't recommend this for everyone. Most people would burn themselves out trying to do them ALL at once. I'd say focus on perhaps two at a time, perhaps switching to other sets of dailies if you're getting bored of the ones you're currently doing. They're all worth doing, ultimately, but none are really required. The game's not going anywhere anytime soon...take your time.
Currently I still do the Golden Lotus dailies every day, mainly because I'm still collecting Skyshards. Once I've gotten them all and picked up the mount I might drop them altogether in favor of the 5.1 dailies unless I need quick cash again.