The fresh berries, especially if you use them whole, will make the cake much more tart. I love using fresh cranberries but always chop them or at least cut them in half. I've found a whole berry bursting in your mouth can be a little too sour!
Unless the recipe called for soaking the dried cranberries first, your cake will be a little more moist. Probably not to the point it's a problem, though.
If you decide to use fresh and cut them, be sure to do it frozen--it's SO much easier! You can mix in frozen berries just as you would thawed.
-A balanced diet is a cookie in each hand