I'm playing Old World Blues at the moment, and it's good. I love the dialogue and chatter with the computers, but the glitches are starting to get to me. I had maybe three times in the main game when it completely froze, a few times when I was stuck in objects, over a play time of 70 hours.
In the five hours I've put into Old World Blues the game has frozen three times. At least five times when I've gone into VATS and fired, my character stands there doing nothing, and starts doing what I can only call a seizure. The character jolts and vibrates around, and ends up with his feet above his head and gets hacked to death after not firing a shot. Then I walked onto a rock in the middle of the area nowhere near the border and I fell through and got stuck. Keep in mind I'm still enjoying it mainly due to the robots and their stories, and also getting to try out my .50 match grade rounds on lobomites, but it's not perfect.
I haven't played Honest Hearts, but I would disagree about Dead Money being bad. I had quite a bit of fun with it, I didn't get many useful weapons or items aside from the gold, but it had an enjoyable story, good gameplay, and interesting characters. Part of that may be because I loved Thief, and the scrambling around in dark towns full of poisonous gas avoiding people made me think of Thief while I played it. The atmosphere made it for me, the environment was dark, rundown, despondent, and in the case of the gas it was aggressive. The gas seemed like what the radiation should've been, it will kill you, no spending 5 minutes in it and then running out and popping rad-away.