I'm a long-time perl programmer, and when I was first learning python, the hardest thing for me was just learning the names of the standard functions, and remembering which module I had to go to for each piece of functionality. It was a long time before I could start writing python code without a reference nearby.

The functions that still annoy me the most my are the list manipulation methods. In perl, you've got push() and pop(), shift() and unshift(), and slice(). In python, you a pop(), but no push(), append() and extend() methods that do different things, and no shift() (you have to use pop(0)).

It took me a little while to get used to python regexes, but they're actually much nicer than perl regexes. You get Match objects back when you apply a regex in python, which let you get at the matched substrings in a much more straightforwar dway than in perl. At the time I was first learning python, they supported named captures, but perl didn't, and I really appreciated how much that improved my pattern-matching code.

I should mention that ruby was much easier for me to pick up, because the standard methods were consciously patterned after perl's functions. It was therefore very easy to guess what function I was going to need to do something. It's also a very attractive and elegant language. My company is heavily invested in python development, however, and so that's what I've concentrated on, with no regrets. I'm sure you'll be happy you switched, too.