The first season was one of the best videogames I've ever played. The character development was great, the choices you made actually MATTERED, and it made me cry like a baby at the end. Lee was a great character and he will be sorely missed.
As for the second season, what manner of atrocity was that pile of shit? They needlessly killed off characters like Luke and the plot was a complete mess. The main villain only lasted for two episodes, for crying out loud. The second season was a huge disappointment and is the main reason why I didn't want to waste my money buying the third season.
Overall, the third season is so far a huge improvement from the second season but far behind the first one.