The actual migration from WordPress to Blogger was very easy. The hard part was actually finding the information on how to do it. With a medium to large WordPress blog, a little bit of technical knowledge on running command line scripts is needed, but here are the basic steps:
First, from your WordPress admin dashboard go to Tools > Export to generate a copy of your existing blog in XML format. By default, WordPress exports everything including all the spam comments so I suggest you delete all the spam comments first (goto Comments > SPAM and delete them) and then do the export. Some of the spam comments had bad data in them that could cause problems when you try to do the conversion to Blogger's format. This was what caused me the biggest headache.
Once you have your export file, head over to http://wordpress2blogger.appspot.com/. This is an open source project that will convert your WordPress export file to Blogger's import file. Note that if your export file is greater then 1MB (most likely), you will need to download the script used by the site and manually do the conversion yourself (see below).
In your Blogger dashboard, simply import the the converted file and you're all set!
Manually Converting to Blogger Format
To manually do the conversion, you need to have Python which is commonly available on Linux and OSX, but doesn't come default on Windows. Once you have Python, you need to get the Google gdata client. Go to the directory where you have the client and run:
sudo python setup.py install
You now have everything ready to do the conversion! Download the conversion script from http://code.google.com/p/google-blog-converters-appengine and from where you uncompress the file do:
bin/blogger2wordpress.sh <you file here> > blogger_import_file.xml
Go to your Blogger dashboard and import "blogger_import_file.xml".