I don't mine. So I can't answer your question 'as a result of mining'

But it sounds to me like you are about to take the plunge and want to know "is this shit for real? Can I really sell bitcoins for real money?"


Do this:

1.) Open an account on mtgox or tradehill.
2.) Buy Bitcoins
3.) Wait a day.
4.) Sell Bitcoins
5.) Withdraw EUR/USD from exchange.

You will see that you can, in fact, trade BTC for USD.
As far as mining is concerned, It'll only be 1,4,5


As far as "is mining actually profitable?" That's a whole other enchilada.

EDIT: Re read your post to see you aren't actually solely focused on mining. But the answer remains, yes, there are always buyers for your bitcoins (or there have been so far)
I still recommend doing the above so you can see that step 4 is actually the easiest part.