PowerShell Script to Check Email Blacklist Services

Not being a fan of getting blacklisted and not wanting to pay money for the service I put together a little script to check a list of blacklisting services. I thought I would share with you fine people. Please let me know if you have any suggestions, I'd love to hear them.

http://pastebin.com/gfM3q4wn

I have it designed to take a list of MX records as a parameter or you can hard set it as I do and it will get all the IP's from the MX records, and use that to check the list building an array and emailing you if you're found. I have it as a scheduled task running every 15 minutes.