I like what Zed has put out, but the books Lutz has out are great as well. Hetland's book is OK and Paul Barry's "Head First Python" is a great read if you're a true beginner to get your feet wet with a fun book. It's an easy read, but I would think that the transition to "Learning Python" would feel like a slight step backwards - however "Programming Python" by Lutz may be a better logical step (instead of going back through a lot of the basics).
I could use the official python library  but I usually prefer reading away from the computer and then getting back to get some actual work done; so I am looking for a dead-tree book.
Currently I am thinking b/w PER  or PSL by Example . I see that PER gets referred to everywhere but that could also be due to the fact that it came out in 2009 and PSL by Example just came out last month.
On a quick look, it seems PSL by Example gives more of a tutorial feel (which I think is great!) whereby PER is essentially a reference. What would you recommend?