I have been seriously impressed by geckoboard, but do not have anything serious enough to use it on and so would be unlikely to pay much for it (for the time being).<p>One other thing is that if I was using for something serious, I may be worried by geckoboard having access to some of the more sensitive data. I think this could be a big deterent for some.<p>Overall, you have an absolutely kick-ass product, I suspect that if you dropped the prices a fair bit then even the most casual users would sign up, which should result in greater revenue for you.
This article is a good read on pricing: <a href="http://onstartups.com/tabid/3339/bid/37737/Secrets-Of-Freemium-Pricing-Make-The-Cheapskates-Pay.aspx" rel="nofollow">http://onstartups.com/tabid/3339/bid/37737/Secrets-Of-Freemi...</a><p>Per-device pricing means your users need to make a pricing decision every time they add another device, which they may hate and try to avoid.
I have been using Geckoboard for a few weeks now but, sadly, none of my ventures have enough traffic for me to see the value in paying for the service (at this point). I believe that it is an awesome product but I believe the price barrier is going to be a huge deterrent for average webpage owners. You might consider going freemium and perhaps allow only 1 site/account up to 1000 views/day (these numbers are only to get my point across). The hope is that you gain a larger user base, including many who would have to upgrade if/when their sites get traction.