Yes you can migrate all of your information including preferences. There are two tools that are very similar but do have differences. The first is Setup Assistant, this begins when you turn on any Mac for the first time, part of SA is it will ask if you are migrating from another Mac or PC. If you answer yes and follow the on-screen directions your new machine should look like the old machine. However if you skip this step you have another opportunity, you can use Migration Assistant (Applications - Utilities - Migration Assistant), this does basically the same as SA except it will create a new user account.
Here is an article from Pondini that explains the two tools, if you have not received the new iMac yet I urge you to use SA. Lion or Mountain Lion Setup Assistant tips