Will a person see any performance difference between the 1GB Green WD and the 1Gb caviar black WD?

Depends on what you are using it for. Unless you care about a couple watts or heat is a problem i would go with the black edition though as the price is just about the same and the performance is supposedly better.

Here is a comparison (last page has some comparison charts, not sure they relate to real life well though).

http://www.thetechlounge.com/article...ors+of+Caviar/