I recently bought a job lot of cards and a couple of them have a christmas bauble on the text section of the card. it looks like a stamp but the text appears to be printed over the top. is there any signifcance to this?

I can't address whether the text is really over the top or not, but many large events will pre-open boosters, inventory them, and stamp them so that the cards may be identified as official cards for the event (prevents anyone from sneaking cards in). That might explain it.