To be disappointed that they used existing DNA to do this is uninformed. We are so far away from synthesizing a completely novel form of life from scratch. This step is needed before we ever get close to designing our own cell — it's the leap from using hand tools to CNC.

I agree that disappointment in this accomplishment is crazy, it's an amazing feat

That said, people can sometimes go batty and start thinking something was achieved when it wasn't. I think it's reasonable to clarify that this isn't a full realization of "artificial life" just yet (though it clearly is a partial realization, as the scientists did alter the genome (also, apparantly they removed potentially disease-inducing strands of DNA, according to the NYTimes). The poster who got negged expressed this distinction in a fairly dismissive fashion that appeared to disparage the achievement. But you should be able to point out (diplomatically, one would hope)that a monumental achievement isn't an even more monumental achievement without being accused of minimizing the achievement itself!

Some people won't be happy unless they make their OWN protons, neutrons and electrons instead of using existing ones in their artificial life.