Hey, I just signed up for an account here and thought I'd post my decklist and a mini-report for what I saw of this tournament.  I was one of apparently 5 affinity decks--I took the deck expecting to have some fun but not be too competitive, and I was quite happy with my 4-3 finish.  I actually saw 3 mirror matches, which I'll discuss in a minute.  First of all, here's my decklist:

"Affinidraw"
Mana base (23):
4 Glimmervoid
3 Seat of the Synod
3 Vault of Whispers
2 Underground Sea
1 Volcanic Island
1 Tolarian Academy
1 Mana Vault
1 Mana Crypt
7 SoLoMoxen

Creatures (15):
4 Arcbound Ravager
3 Disciple of the Vault
3 Frogmite
3 Arcbound Worker
2 Myr Enforcer

Draw engine (17):
1 Ancestral Recall
1 Timetwister
1 Wheel of Fortune
1 Memory Jar
4 Thoughtcast
2 Thirst for Knowledge
4 Skullclamp
3 Genesis Chamber

Other brokenness (5):
1 Time Walk
1 Tinker
1 Demonic Tutor
1 Vampiric Tutor
1 Yawgmoth's Will

SB (15):
3 Rack and Ruin
3 Red Elemental Blast
1 Blue Elemental Blast
2 Fire/Ice
4 Blood Moon
2 Stifle

As I was tuning the deck towards this build, I realized that it really worked more like a combo deck than aggro: in a good game the deck should "go off" and I should be drawing through most of the deck in one turn (plus Time Walk turns!) to power a Ravager-Disciple kill.  The skullclamps and genesis chambers are the real key here, and all the draw spells fill in the cracks.  After playing in the tournament, I think I might take out the Myr Enforcers for a full set of 4 Frogmites and 4 Workers (or 4 Disciples), and since the Tinker's only real purpose is to resolve Memory Jar, I could probably replace those two cards with one Windfall at only a slight loss of effectiveness in exchange for another slot.  Also, Rack and Ruin is NOT the right answer to Null Rod--I wish I had included 3 Shatter or Shattering Pulse in the sideboard.

In the tournament this deck won handily against one Fish deck (to be fair, he was inexperienced and got bad draws, and I had the best draw I saw all tournament), lost to a "Where's the Fish?" variant, lost to Mono-Blue control, won against Grow/Tog, won against an Affinity deck not too different from type 2 Affinity, and traded matches against two Ironworks-Affinity decks.  I didn't see any Stax or other Workshop decks (other than the Ironworks-Affinity decks running Workshops).

Like combo decks, I found that if I could play more or less unobstructed, I would "go off" turn 2-4 and get the win; two of my losses were due mainly to well-aimed counterspells plus Null Rod in one case and Energy Flux in the other, and one Ironworks-Affinity deck just went off faster than me two games in a row.

So, for the sake of those who are interested in Affinity as a type 1 archetype (I saw a couple of older threads on it...), here's my analysis of how the builds I saw stacked up against each other:

One of my mirror matches seemed to be basically type 2 affinity plus power.  He won one game resolving two early Myr Enforcers and beating with them before I could go off, but the two games where I got decent draws I had no trouble going through my deck to find my kill.  From my perspective, Affinity as a combo-ish archetype seems much more powerful than trying to go aggro with it.

The two Ironworks-Affinity decks I saw were very similar to mine.  The builds seemed pretty close except for a few key differences: they ran Workshops and Krark-Clan Ironworks for a higher-powered mana base than mine (if I had managed to get my hands on some Workshops before the tournament, I would have tried them out...), and they killed with Ravager + Triskelion rather than Ravager + Disciple(s).  The main draw engine of Genesis Chamber + Skullclamp + supporting spells was pretty similar.  In these matchups, it pretty much came down to which deck could resolve a Yawgmoth's Will, Time Walk, or draw-7 first (usually turn 2-3).  I think the Ironworks worked very effectively and I plan to play around with them in my deck, but I still have more confidence in Disciple for the win over Trike.  The main reason is that each point of life loss is its own event (and each artifact is worth one point of Ravager attack damage plus one point for each Disciple I have), whereas the Ravager + Triskelion can be totally countered with a well-placed Stifle (on the Modular counter transfer, of course!).

So...I hope this writeup was interesting for the crowd here.  I'd be very interested in hearing more thoughts about Affinity as a type 1 archetype...it seems to me that it has decent potential, but I'll admit it's still a bit fragile in the face of disruption (Null Rod, Energy Flux, or a few counterspells can be very harsh, though land/hand disruption isn't as much of a problem).  Suggestions on how to improve its robustness would be appreciated.

P.S.  It amused me very much that my opponents started Mana Draining and Forcing my Frogmites and Arcbound Workers...and those definitely were the right plays at the time!

P.P.S. Grazie to a friendly and experienced Italian named Lucio who helped me tune the final decklist.