A metacoin is the same as a user defined coin. There is no difference. You can bet with a user asset versus another user asset.
Anyone (IXC foundation included) can chose to distribute a new asset in any way it pleases. Via burning IXC, by paying a fee, etc.
No, it is not. How many times we need to go through this?
A metacoin is not issued by anyone, it is created within the implementation. Therefore it is not controlled by anyone, and it will exists as long as the protocol exists. Any user definied asset is issued by someone, and requires trust to the issuer (additionally with some legal implications). I could issue a coin mimicin my proposed metacoin 2b), but I can also cancel the coin at any time. I'm sure you can imagine reasons (mob/feds, my family) for doing that.
You need to clarify the difference between issuance and distribution.
With Bitcoin, technically the developers issued 21 million coins and provided sha-256 mining as a way to distribute said coins.
With Counterparty, the developers issued counterparty coins based on a formula that was a function of burning coins. The distribution was performed by the actual burning.
Some random dude can issue a coin and have it distributed by some random event occuring in the block chain.
Issuance is always performed by a human who codes it in as a specification.
Distribution can be done by some formula ( proof of stake, fixed market price, proof of burn etc).
The Fed issues USD money printing... but it is distributed via Open Market Operations (i.e. Treasury auctions).