Hey I remembered to update this every day this week yay!
*Ahem* So it's the last day and what have we learned? That you DO have options when bringing your magic afterbirth into the world. I offer you a final wrap up.
My personal opinion is to just do it all yourself. You will ultimately end getting what you want in every respect. If you build it (and it's a hit and you pimp it right) they will come.
However if you have no artistic vision and just want quick cash the distributors are there for you. (just don't expect long term income) If you are tapped by a magic company just remember to read the contract carefully. Some of them will give you cash up front as a buy out and that's it. Others will offer you a percentage. Make sure you know what you are getting into.
The biggest advice I can offer up is to sit on your creation for a bit. Really decide what's best for the community and art, not your bank account. If it's a variant, just hold onto it and put it into a collection of things. If you are gonna explode if you don't share it, try a download. That way you can keep the cost down and not clog magic stores with "just another card trick".
Now go forth and don't multiply!