All the plants I got, apart from one, didn't have wires in them. I made sure I checked before buying, but the one that did, I carefully used an exacto knife and removed the wire, then reglued the plastic stem with aquarium silicone. Not the quickest thing to do but it worked. I'm not sure what would happen if you left them in, although it would rust.
Hey. From what I remember, you have some silk plants from Michael's, right? I just bought some, and I was wondering...What did you do with the little wires that were in the plant? Is it ok to put that in the tank?