yes.
because yes.
Left4dead is a great series, with the ability to tell a story only valve can. Same reason I like half-life. telling stories withing a story. Admitted, the left4dead story is . 4 chumps are lost with zombies, get to tha choppaaaaah. But the comics and extra content make the game more.. well.. great. The survivors get along so well and can even positively interact with fellow survivors (1+2). Not many games can pull that off. And yes Francis and Nick are pricks, but even with their prickery, they are still good for the group's solidarity, and by being ,if unwilling, part of the team, they still manage to put aside their annoyances, for the most of the time, and help/save others.
And that is why i like left4dead, and will be buying the possibility of 3.
also it's fun! and it pisses off my dad, because he thinks killing zombies is bad. so; More fun!
TL;DR
I liked l4d1/l4d2, and I will like a possible 3.