I agree it’s a good job for a first try. The subjects are too close to the green screen so you have some spill issues. I realize you didn’t shoot it but the people who did, didn’t do a good job. I would add the Chroma Bur before the Chroma Keyer and add a Horizontal Blur. This will smooth out the jagged edges, especially on the second talent.
NewBlueFX has a nice keyer with spill suppression that won’t break the bank in the Video Essentials II plug-in. You might want to look into it. There is a free trial you can download and see if it does a better job.
~jr
http://www.johnrofrano.com
http://www.vasst.com