Take a look at a thread on Kotaku about when World of Goo did a "Pay what you want" sale to celebrate it's birthday. I think the most common paid amount was $5, with a good number of people also paying $10 for the game... when comparing numbers, WoG received a ton more PROFIT from those spending $5 on the game... my advice is to low-ball your opening price ($5), so significantly more people can't resist picking up a copy. Secondly, on the "Top Grossing" chart right now, you have Rock Band and C&C on top ($10), with Ski-Ball ($1) and Tetris ($5) near the bottom. The three more expensive apps are long-running, known franchise, while Ski-Ball appeals to the very wide audience of casual gamers. Ravensword has gotten a lot of buzz on iDevice sites, but your name is not "household" and your game will not appeal to the casual crowd. In summary, low-balling your opening price should help sales dramatically. $6.99 is a good price, but $4.99 is a deal I can't pass up... my vote is for $4.99.
Also, pricing at $4.99 captures business from 31% (the percentage voting for $5) more people who voted in your pole.
A bit of math here: 1) If you price the game as it will be (6.99) you will get 69% of the poll respondents. If we convert that to 69 customers to keep things simple, revenues come to $482. 2) If you price the game at 4.99, you will get 100% of the poll respondents for a revenue of $499. Here's the thing: the devs may make a little less money with option 1, but they still gave the option of lowering the price to 4.99 in a few months time and getting the remaining 31% for an extra $195 (Total: $677). As a developer, would you prefer to earn $499 at once, or $482 at once and $195 later? For some games it makes sense to price the low initially to get them in the public's eye. For a game like this one, which is already much anticipated, that makes little sense. Frankly, this thread should probably be closed, as a decision in pricing had already been made.
If you believe your game is better than the competition and there is adequate demand for it then price it higher. I would go with $12.99. Good quality games need to start breaking the $10 mark. If the game is worth it then the sales will be there. Stick to your guns though. You can always put it on sale in like 6 months. Just don't do the daily price filp flop. That will just annoy gamers that paid a higher price.
I buy a lot of apps, and I don't mind spending money on apps. I have never taken a promo code and actually get a little repulsed by the feeding frenzy that arises any time a developer offers a promo code. I tend to feel that if I want a game, I'll pay for it to help support it. I also pretty much never wait for sales unless I'm unsure if I actually want a game. In those cases, I probably won't even buy it on sale because I didn't really want it that much to begin with, but occasionally I will. That said, the reviews of this game would have to be incredible for me to consider spending over $6.99 on it. I've been burned by a LOT of independent developers who's games don't quite live up to expectations, and small development teams often don't have the time or resources to make as fully fleshed out/polished games. I would never even begin to contemplate anything above $9.99 for an iphone game. I love my iphone, I love gaming on my iphone, but the best games on my iphone are not worth more than $9.99. The coolness factor of iphone games is that you have them on your phone, but even the best are limited and harder to control than games on dedicated gaming systems, and I couldn't see spending more than $9.99 on any of them. Even having $12.99 and $19.99 on the poll seems ridiculous to me based on the current iphone pricing structure. Hopefully this game turns out incredible, and good luck with it. If you launch it and the reviews are phenomenal, you can always raise it to $9.99 with customers fairly certain of getting value for money.