Ideally, I'd like come out of the gates with an entirely free application, and let the community help shape the direction of the product. However, if I impose caps after the fact, I'm in a position similar to Zoto where I've burned the people who have helped build my product.
If I do a closed beta, or come up with an arbitrary hierarchy of caps and prices up front, I'm afraid it'll hinder adoption.
Any insight into the best way to impose caps? Feel it out after getting some users? Sooner rather than later?