A lot of it is personal taste. I've seen a few lcd's with excellent pictures, but for the most part I think the plasma's look better overall. I've also seen a few plasma's with poor pictures. The lcd screens have made a lot of improvements lately and are getting better. There are a few that are excellent, but again, as a generalization if feel safe saying plasma screens usually have a better picture, IMO.
I'll still probably get a lcd. I'm paranoid about plasma's because i fall asleep and leave static images on regularly for extended periods. I'm not yet willing to risk to possibility that the screen will be ruined/damaged.
Jack