I picked up the paid for DLC a few weeks ago. I enjoyed it well enough. I liked the new weapons and missions. Honestly wish they'd make Kasumi a proper character as opposed to a DLC one, because it would give some time to actually explore the character. (as has been pointed out above, there are some problems, but I think the problem is that she's never explored, rather than her being incoherent. Interesting humans are always full of contradictions) I think DLC characters that function like Zaeed are a mistake, because I don't know about everyone else, but half the reason I play a bioware game is for my party. I'd rather have less, supremely fleshed out characters than more one-liner spouters, please. I'll definitely be picking up lair of the shadowbroker, but I would love some real -substantial- content that gives me a chance to affect the universe and takes more than an hour to run through. I only grab this stuff because it's pretty cheap. And even then, I feel it should be a bit cheaper for what you get.
Like I said, I enjoy it, but not unreservedly.