Someone asked me to make an attempt at ranking the games I've played so far from the Essen crop (kind of like Valerie did over on www.boardgamenews.com).  While I can't create a strict order like she did, here's what I can give you:

Excellent Games - These are games I want to play again (and have) and picture on my shelf permanently:
Cities - Tile laying (a plus), short, and some interesting puzzle-y aspects.
Ghost Stories - beautiful, cooperative (but can be played reealistically with 2), and HARD
Lungarno - another tile laying game with straightforward rules that spark familiarity and newness.  Another good 2-player too.

Very Good Games - On the shelf for the long haul, though may fall by the wayside.  Might be too early to tell:
Aber bitte mit Sahne - probably belongs on the list above, but I've only played this with 5, so not sure how it scales.
Bloom - Shelley liked our one playing enough to request it for Christmas (Woo Hoo!).  That's a big plus, but we'll see how it works with 2.
Heads of State - My hands down favorite from last April's Gathering (in prototype).  Shines with 4-5 players, but is rather long.
Space Alert - Need to play this more, though it's not Shelley's type of game so that may mean specially-scheduled playings....
Snow Tails - Best of the racing games out of Essen that I've tried.  Fun theme, easy mechanism that still leads to those "D'oh!" moments.
Tenakee - Fun Amigo filler about building/capping Teepees.  Choose your cards for each round, then see if they can pay off...
Via Romana - Deserves another couple of plays before a true decision is made, but we really enjoyed the first playing of this.
------I wish Goldseiber could get their act together and have their games published over here more readily.
Wasabi - The jury's out on its nastiness with the Wasabi card, and there may be an AP problem with certain players, but this is gorgeous!!!

OK or Further Plays Definitely Needed:
Boss Kito - It's Schacht (+), but the start player rotation can feel broken in some plays.  May be best with 4.  Jury's still out.
Dominion - Not my type of game and DEFINITELY not Shelley's type. That plus big box = no need to buy.
Fast Flowing Forest Fellers - Meh...with tons of screwage.  No need to buy.
Hab & Gut - Have to try this one again - messed up a rule in the first game that set a bad tone.  Hopefully more interesting than first thought.
Im Wald da sind die Rauber - Hex-laying boardgame with some of Mesopotamia's concepts of pick up & delivery.  Meh...No need to buy.
Sylla - I need to try this again (may have just been grumpy), but boy did it rub me the wrong way on first play.
Voll Verladen - somewhat meager entry by Adlung this year.  Cheap & small (+), but not much of an interesting game.
Zack & Pack - I really want to like this, but...I've discussed my concerns elsewhere.

Not My Style or No More Plays Needed:
Genji - OK, may be interesting as a 2-player, but with 5 it's fairly deadly.  i wanted to like this (poetry with innuendo?) but just enjoyed the company (Janna, Michael, Simon, Shelley) at BGG.con
Mehr Oder Weniger - Set-like game of looking for shapes/colors on card that are flipped.  OK for kids & small Adlung.
Middle Kingdom - TOTALLY convoluted.  Could be interesting for Magic players as majorites add various (pay attention!) powers. Meh...

Essen Games I STILL need to play (can't wait for Winter Break!!!):
After the Flood
Batavia
Carpe Astra (graciously donated by Reiver Games!)
Chicago Express
Circus Maximus
Comuni
Confucius
Crash by Crash
Duck Dealer
Galaxy Trucker Expansion
Hexer von Salem