Some tried-and-true picks...
Fast aggro: The basic idea here is to overwhelm your opponent with repeated attacks by low-cost aggressive creatures, backed up by some efficient removal to clear the way, and maybe a bit of burn to finish him off. Fundamentally we're describing a Red Deck Wins strategy, so it shouldn't be surprising that red-black and red-white tend to be the strongest colors for this approach; you can do without red but you really have to go all-in on good weenie creatures to do so. The bedrock of this archetype are cards like Diregraf Ghoul, Reckless Waif, Vampire Interloper, and Cloistered Youth. For the higher end of your curve, try to pick up creatures that can help you push through more damage, like Crossway Vampire, Instigator Gang, and Morkut Banshee; undercosted beaters like Galvanic Juggernaut are also good. Brimstone Volley absolutely rocks in this deck, but also keep an eye out for Geistflame, Dead Weight, Bonds of Faith. In play, be aggressive and try to win as fast as possible. Cards like Rally the Peasants and Nightbird's Clutches are also good, but don't short yourself on creatures in order to play them!
Evasive beats: This is the same strategy as "blue/white flyers" in a number of other sets. You use hard-to-block creatures to consistently get in some damage with flyers (e.g. Voiceless Spirit, Stitched Drake) while sandbagging your opponent with blockers (e.g. big-butt creatures like Fortress Crab, spirit-makers like Doomed Traveler) and controlling spells (e.g. Bonds of Faith, Claustrophobia, Sensory Deprivation). Take note: Invisible Stalker and Skaab Goliath are also "evasive" creatures! This deck can generally afford to run more auras and equipment than most decks (especially if you manage to pick up Stalkers), though you should be choosy with your picks; Spectral Flight and Curiosity are both good. Unlike the fast aggro deck, you don't so much want to rush to a win as cruise to one.
Midrange beats: Basically this is an deck that spreads its threats out across the curve, beating other aggressive decks with its ability to "go bigger" while still having enough pressure to punish slow decks. You can do it in various colors, but green tends to be a solid choice because of the density of beefy creatures like Festerhide Boar. You can make a pretty cool tribal deck with white-green humans-and-werewolves, thanks to two human lords (Hamlet Captain and Mayor of Avabruck) and cards like Elder Cathar and Gatstaf Shepherd. Some token-makers (even if it's just the lowly Doomed Traveler) can help . Avacyn's Pilgrim provides the deck with some much-appreciated ramp.
Mill yourself: Here's an archetype that's very specific to Innistrad. You want to use cards like Forbidden Alchemy, Mulch, and Curse of the Bloody Tome to fill your graveyard, then, erm, do stuff with that. Your options for "doing stuff" vary. Initially conventional wisdom was to draft flashback spells, but it's not that effective: most Innistrad flashback spells are priced to be cast affordably from the hand, and then flashbacked a few turns later as a bonus. Milling yourself just to pay 8 for a Grasp of Phantoms is not a good deal! What does work pretty well is creature-based self-mill. Self-mill in a creature-heavy deck fills your yard up with cards you can use to reliably cast those sweet Stitched Drakes and Makeshift Maulers, while cards like Gnaw to the Bone, Spider Spawning (splash black), Boneyard Wurm, and Kessig Cagebreakers take great advantage of the massive number of creatures in your yard.
And, on the sketchier side...
Control: You're not going to be able to draft a perfect imitation of a Constructed control deck using the card distribution in Limited, but I think there's room for a control deck in the environment. Blue and black are the classic control colors; in Limited, red is also important because it has the broadest access to removal effects. Don't write off any color, though, because the real goal here is to pick a bunch of best-in-class answers that you can use to dominate the board. Rolling Temblor, Victim of Night, Claustrophobia are examples of removal cards you'll want. Innistrad isn't as bomb-focused as other formats, but a big crazy rare can really make your day -- Olivia Voldaren, Reaper from the Abyss, Balefire Dragon, Bloodline Keeper (if you find yourself unable to go red/black aggro), maybe Ludevic's Test Subject; Skaab Goliath works in a pinch. You'll also want to run some low-cost creatures for defense, such as Typhoid Rats and Delver of Secrets/Stitched Drake (depending on your creature-vs.-spells density). Play Forbidden Alchemy and Civilized Scholar to help you dig for answers. Since you're running three or more colors, you'll want mana fixing (Traveler's Amulet, Shimmering Grotto).
Tempo: Basically you play some awesome cheap creatures and then use bounce, removal, and some counterspells to slow down your opponent while you win the game. Delver of Secrets is common, which is what really enables this deck. Cheap flashback spells like Silent Departure are good. I wouldn't do this as a first-choice strategy, but it's a fun deck to build if you find yourself with several Delver-level creatures but lacking the cards to go full aggro.
Flashback combo: This is a "garbage man" strategy relying on Burning Vengeance and loading yourself up with flashback spells nobody wanted to pick. Some self-mill can help, but, again, watch the flashback costs.
