Uh oh. I would say no, it's probably the most harmful action you can take to bring about racial equality.
In the workplace, I definitely agree. In the colleges, I think it is debatable. Dependency on the Gubment is an intrinsic value for some cultures within our society. Making sure a few people from those cultures makes it through college is arguably cheaper than paying the costs associated with lifelong government dependency for those same people, not to mention it aides in fundamentally changing the culture. There is a reason why our colleges are so jam packed full of Asians.
Yes, it has had an undeniable positive effect either way the subject is spun and should be continued as long as any inequality exists to counter the bias's that led to its inception.
I hate to sound like some social engineering Democrat, but certain ethnic groups generally speaking either don't apply, or don't meet the ever rising bar of admittance causing a dramatic under representation. Normally I would say, this is America. Apply yourself and you will do well. There is a fundamental cultural legacy within those groups, IMO, that frowns on trying to do well. Aside from the financial benefit of not having those people on welfare I mentioned earlier, pushing enough of those people through college could go a long way to fundamentally change the culture within those groups. Scholarships alone wont do it. On a side note, the same thing generally works on devout Muslims in America. By the time they get out of American public primary education, and certainly by the time they graduate from college, education has taken the Mohammad worshiping, woman beating, airplane bombing tendencies down several notches for those with a modicum intelligence. Not that putting them all through college is an affordable or feasible solution, but if you get enough of them through college, you can change the culture entirely.
I think affirmative action in the workplace should be abolished. I believe it has done all that it can and now only give racists (from all sides) something to keep the fires going. The white racist business owner, as long as it isn't a large business, can get past it still and any other colored racist (yes, racists come from all races....) can always skirt the law because it doesn't apply to them.