Oh, so it's that one. Fine. Yes, you're right. It didn't free a single slave. It's significance was purely symoblic. But as a symbol, it was a powerful one. Here's what Frederick Douglass said about it, "and in the fullness of time, we saw Abraham Lincoln, after giving the slave-holders three months' grace in which to save their hateful slave system, penning the immortal paper, which, though special in its language, was general in its principles and effect, making slavery forever impossible in the United States. Though we waited long, we saw all this and more.
"Can any colored man, or any white man friendly to the freedom of all men, ever forget the night which followed the first day of January, 1863, when the world was to see if Abraham Lincoln would prove to be as good as his word? I shall never forget that memorable night, when in a distant city I waited and watched at a public meeting, with three thousand others not less anxious than myself, for the word of deliverance which we have heard read today. Nor shall I eve forget the outburst of joy and thanksgiving that rent the air when the lightning brought to us the emancipation proclamation. In that happy hour we forgot all delay, and forgot all tardiness, forgot that the President had bribed the rebels to lay down their arms by a promise to withhold the bolt which would smite the slave-system with destruction; and we were thenceforward willing to allow the President all the latitude of time, phraseology, and every honorable device that statesmanship might require for the achievement of a great and beneficent measure of liberty and progress."
http://members.tripod.com/~american_almanac/dougorat.htm
And given the way the south squawked over the proclamation, they certainly saw what it meant--that when the war was over, slavery would be ended.
It's significance was purely symoblic. But as a symbol, it was a powerful one.