In the future they may remove the "under God" phrase. In the past 15 years or so, many courts have eschewed people swearing on the bible to simply holding up their right hand and promising to tell the truth. As we become a nation of more atheists and alternative gods (Allah, etc) they may very well remove "God" from the pledge of allegiance and money.
This could never happen in a small-minded country like, say, Trinidad & Tobago, though. "God" will forever remain in their national anthem and currency.