From Deutsche Welle. New euro notes will go into circulation starting in 2013. The new notes are designed to combat the rise in counterfeiting.
As an amusing observation – the bill shown in the article is a 600 euro note (no such thing) and the images on it are much more interesting than anything on the real bills.
I usually have a few notes left over after a trip but this time I only had one ten-euro note unspent. That was partly because I put most of my euro cash on a pre-loaded debit card from Travelex. Slightly expensive, but worth it for the convenience. You just have to be careful that you don’t run out because these cards are not easily reloadable and, depending on where you get the card itself, ATMs often can’t see what the balance is. I have less than two euros left on that card! The way you find out is to try to use it and it gets rejected but, again, no balance.