Good TV shows

Whatever happened to quality sitcoms?  I grew up on Good Times and MASH reruns.  The first good sitcoms I remember in real-time were Cheers and the Cosby Show.  Then came FOX with Married with Children and the Simpsons.  Later on came Seinfeld.  After that nothing.  My girlfriend loves "That 70's Show", but I don't see what's so great about it.  The network dramas were good for a while too--Dallas and Hillstreet Blues (which I barely remember), then St. Elsewhere, then L.A. Law, and Twin Peaks (which I worshipped).  A bunch of Law and Order shows.  All good stuff.

I work late, so I get home just in time to see the Adult Swim reruns at 2am.  What am I missing from prime time?  I hear "Lost" is pretty good.  I'm a big fan of sci-fi fridays already.  I download all the "24" episodes.  So what am I missing?  What's great with tv these days?

For kicks, there's a poll.