I'd say feel free to use both I agree with ~Sir-Migglesworth. At college we used the term freelance in reference to artists that are not attached to a company/design house/etc. Commissions are little more casual - as in do what you're doing at say a con... and there it is.. no one has to sign on contract, etc.

Freelance sounds more professional. ;3 Freelance means you actually work with companies!

Well, in college we used the term freelance. I agree with Kestral in that it's the term used to describe an artist who isn't affiliated with a company. The artist usually has more imput and influence when doing freelance work but there also tends to be more involved. All the freelance jobs I've had I've had some sort of contract for and have shown my progress in the work to get approval to go on to the next steps. Commission work seems more cut and dry to me, you're told what the person wants and you do it.

Freelance is the actual term for artists that work from home, do not work for a company etc. It doesn't just apply to commercial or fine arts, freelance title gives you the ability to turn down a job, that you believe you cannot do,either you're not skilled enough,or its a job your unfamiliar with.

Commission to me means, that they're paying you so You must do it even if you want to reject it.

agree with morgan, to me they arent exactly interchangable. A freelance is more of a larger scale job, or done more with a business, as in they pull you in to get something done they can not. (now it sounds like a hired hit man XP)
Where as commissions is more of a one time thing, one drawing, for a personal thing.

To me commission sounds more proffessional, Cos it implies finding that you have exactly whats needed at the time, where as freelance implies your filling a hole.

It all comes down to prospective/and or type of client. To which yourself and Mogana have both defined quite well.

I've always thought that commission sounded more fine artist, where as freelance sounded more commercial artist.