Recommended strategies for the MTGO Cube
To provide a different perspective on thesunneversets' answer: the most important concept in cube drafting isn't power level, it's synergy.  It's easy to look at your deck after you've drafted - or while you're drafting - and say 'this is chock-full of great cards, it should be awesome.'  The problem is that everyone's deck is chock-full of great cards; to put yourself above the pack, you need to have more than just great cards.  And that's where synergy comes into play.

It's impossible to provide a full list (or even a reasonable partial list) of the synergies in the MTGO cube just because there are so many there; instead, just look for potential little synergies and combos when you're drafting.  Already snagged Channel?  Keep an eye out for high-cost artifacts and colorless cards that you can run out in the first few turns - surprisingly few decks can beat a turn-2 Ulamog or Karn.  Picked up Recurring Nightmare?  Maybe you want that Myr Battlesphere a little more; maybe Entomb or Buried Alive or even just Careful Consideration bump a bit higher up your pick order.  These sorts of synergies are what you want to be looking for.

This strategy extends to your first few picks, too - there you want to keep an eye out for cards that can synergize with a number of different cards.  I'd cheerfully pick Survival of the Fittest over many other cards in the format, for instance, simply because I know I'm likely to pick something up to go with it: maybe it'll be Vengevine for a green aggro deck (and boo on Wizards for skipping Basking Rootwalla!); maybe it'll be Recurring Nightmare or just Animate Dead for a reanimator deck; maybe it'll even be Myr Battlesphere and Goblin Welder for different sorts of reanimator shenanigans.  Maybe it'll just be a collections of walls, Acidic Slime and its kin, and Birthing Pod up to Elesh Norn for a toolbox-style deck.  But any way it shakes out, I've got good chances of finding something that'll work with Survival.

As far as specific card advice, there are a few things that come to mind:


Artifact acceleration is sparse, and key for the high-end control and board control decks - maybe even moreso than plain fixing is.  Early on cards like Prismatic Lens were being overlooked and you even had a reasonable chance of tabling them, but at this point they've moved much higher up peoples' pick orders and need (and deserve) to be picked highly: I've gladly first-picked Grim Monolith - and then used it to cast a turn-3 Grave Titan in multiple games.  The non-accelerating mana fixing (duals, fetchlands, etc.) is important especially for many-color decks, but I've tried to avoid splashing beyond 2 as much as feasible, so it's been less crucial for me.
Similarly, being able to delay color commitment for a bit is a useful thing - cards like Wurmcoil Engine and Myr Battlesphere are high picks in part on raw power, but even more because they're universally applicable, and I'd gladly snag either with my first few picks.
Artifact removal has some value, but most people leave enchantment removal (unless it's something universally versatile like Acidic Slime) in their boards, and many decks don't even have access to that sort of effect.  Because of this (and of course the general power level of the creatures), the control enchantments - Control Magic and Treachery - are even more powerful than they might appear at first glance.
The red deck is strong and it is the clock of the format, but it doesn't seem like quite the beast that people are making it out to be.  If one person is drafting it then they get all the goods, but there isn't enough redundancy in the MTGO cube for it to comfortably support multiple drafters; if you don't have Goblin Guide or Keldon Marauders, for instance, then you probably won't be nearly fast enough to keep up with the accelerated high-end decks.  Mind you, I have a mild allergy to red aggro so I can't speak from the other side of the table, but in the few drafts I've played against it I've had quite a bit of success - it's something you have to keep in mind and it does force a reasonable curve, but it's not something to actively fear.