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This is gold dust - THANK YOU!!

Having each on a unique IP isnt neccessary. The only real benefit of having your sites on seperate Class IPs is to break the relationship between them. In your case, sorting the duplicate content issue should be enough to sort out the penalty. The only downfall IMO would be the low link juice value from linking between all 3 sites Greg.

Commas in the URL aren't necessarily at an SEO disadvantage. It might be a good idea to change them for better usability and better CTRs, but as Russ says, I don't think this is an urgent task.