I've mentioned this before but I want to keep beating this drum a bit.
I honestly believe that network effects will cause a dominant currency to have a vastly higher market cap than any other. Ethereum looks like the most believable challenger to Bitcoin so far. If Ethereum works as advertised it will rapidly erode Bitcoin's network as it has uses well beyond Bitcoin's.
This create a problem. Most of the community will have their funds devalued basically completely as this happens. From a loyalty perspective this is important because that community build the crypto-currency economy. From a self interest perspective it is important because devaluing (even if done completely unintentionally) bitcoin will reduce the available investment and entrepreneurial interest in furthering Ethereum based business.
Another problem is the premine. No-one likes it but the core devs seem to think they can pull it off. I fully support their remuneration for building something like Ethereum, but from even a self interest perspective the pre-mine is a bad idea. Ethereum can easily be forked into a clean blockchain and once it becomes clear that it will deliver there will be believable threats to do this.
So I propose the following:
*Ethereum launches with prefunded accounts corresponding to all Bitcoin accounts. Ideally including prefunds (with weight adjusted balances) for Namecoin because it is the only really useful altcoin and Litecoin because of its mining community.
*Ether is premined for the developers. This will still be somewhat unpopular, but if the proportions are kept reasonable relative to the total money supply, the community will accept it.
The major benefits of this:
*Bitcoiners, Namecoiners and Litecoiners now have skin in the game. They want to see Ethereum succeed.
*Bitcoiners are not left with the unpleasant option of selling to an uniformed noob that which is sinking, or going down with the ship.
*The crypto community has capital after Bitcoin dies (assuming Ethereum overtakes it)
*Because they have capital and skin in the game, their incentives to see Ethereum succeed can be matched be funded by their ether balances.