First of all, thanks everyone for the congratulatory wishes! So sweet of you. Sadly, we were rained out at the zoo, but we still had a fun day. (Though mommy is no contest compared to elephants.)
I also wanted to point out this fabulous blog post by my friend, Lauren Baratz-Logsted. She talks about managing expectations as an aspiring writer. (And yes, she mentions my blog, but that's not why it's so good!) Here's the blog.
Now, back to the questions:
Should one expect an agent to do edits of a book? And if so, how much editing do they really do?
This is a tricky question. Why? Because you should never expect your agent to help you fine-tune your ms. If you do, you probably already realize that the book needs work, in which case, you shouldn't yet be sending it out.
That said, yes, most agents will walk you through some changes. How in-depth these changes will be depends on a) how much work your ms really needs (through the eyes of an objective resource - not your mother, who has already doled out lavish praise), and b) how much time the agent has to devote to you.
When my agent offered representation for TDLF, she said that we could send it out "as is," or that we could really make sure that every last detail was perfect... a light edit of tweaks here and there, and then it would go out. Obviously, I chose the perfection route. And as a result, my actual editor (once the book was sold) had very few changes for me. (Something that truly freaked me out. I mean, it finally hit me that people would be reading what I wrote...I'd figured that my editor would take an ax to it, then put it back together, thus reassuring me that it was truly ready to roll.) There's also the sad reality that editors at publishing houses have so many other demands on them these days that they have less and less time to, you know, actually edit. So many agents truly put the ms through the ringer before it goes out.