I think the promotion is a good thing, and I am calling it a promotion rather than a competition because the competetive element is potentially a bad thing here. However I have a few misgivings about the format:
"Realtime Updates" - This is some really great code, but it's intended purpose has a dark side, and knowing you are X shares away from getting Level 2 etc will just prompt some people to flood their communications channels with links because they know they are close. Check chat for the reduced number of onebox links and the increase in the personalised links. I've done this myself, and am not proud. The fact you can check on the other guys too means you can get too involved trying to beat the others, rather than put out genuine content that would be welcome even without a promotion. If the idea is to promote being a good citizen, then the winning citizen by definition would have done it anyway, and shouldn't be doing it merely because there's a prize. Removing the update would potentially stop borderline genuine users from caning the site for 3 weeks then leaving because they won't have a clue if they are caning it in vain or not, whereas a "better" user will carry on regardless.
"New Users" - Obviously you had a brief when setting this competition up, and you will know what your expected outcomes are and what you wanted to achieve. No way to know exactly what these things were, but what we seem to have is an influx of people (some new, some previously dormant) throwing up a lot of content. The "acheivements" for want of a better word for getting X answers voted on etc reward quantity without necessarily have any controls of the quality. If I ruled the world (in my lovely hat) I would like to see the promotion be more tailored to getting people to use the site properly, rather than to use it lots; this should foster the same end result inadvertently anyway. I know this is difficult, but helpful flags and other badges may be a good way of getting the existing audience to use the site better, which should in turn equate to more at the same time.
"Tactical voting" - I'm not saying this has happened, but I am saying when the time comes close to the end, it likely will happen. Someone with the required 4x6 upvotes will find one get's mysteriously downvoted to 5 votes and rules them out of Level 3. I'm raising this now so you are prepared for it, I know votes are supposed to be invisible, but you will for sure get a query I feel. That's not me saying I will do it of course, but it's human nature when a big prize is at stake. And there's the other side too, people not voting for someone who is close to moving up a level in the competition etc as a way to maintain a gap in the scoring.
"Shares" - I've tried to share and point out exactly why I am doing it. Each time I have put shares out on Twitter I have book ended it with non share tweets about AD and the promotion. I don't want to link bait my friends, but I do want to turn some of them into users here. As I mentioned previously, I'm sure a lot of the shares are actually being shared in chat where discussion is pretty busy at the moment. These shares defeat the intended purpose, as they never leave the site, and are only ever seen by existing users. Perhaps a better mechanism is to allow a referal scheme in a future competition. Having a challenge to introduce 2 new users who get say 250 Rep and 5 selected badges within a month of joining would actually be a way to ensure higher quality inrease in visits that results in tangible benefits.
As I have other thoughts, I may edit them in here. Overall I am 70% positive on the promotion. I hope it acheives it's aims, and of course I hope I win an iPad, and further still if I do, I hope I deserved to win on the basis of maintaining very active but more importantly very focussed input to the sites real aims which still stand apart as worthwhile content. I'll still be here after, as I was here before. This is not an "old guard" (I've only been here what 7 months?) piece of disgruntlement against new users though, I hope that the conversion or "sticky" ratio of the more recently active users is increased post promotion. I would hate to see someone with enough free time simple hammer the site for 3 weeks and then hit the sunset with iPad in hand.