To be frank, there were not many real surprises for me at Essen this year. This is mainly due to the flood of information that is readily available on the internet ( and largely due to Eric Martin's awesome Essen updates and preview ).
Russian Railroads did surprise me but only for the fact that it wasn't a train game but a train themed worker placement game. I completely blocked it out of sight once i saw it resembled a train game. A mistake on my part. So for the fact it was a great game, that was a major surprise.
But one big surprise of Essen is finding a small booth that was demoing a game called Shephy.