Romanticism and Post-Modernism have gone tag team crazy on art criticism, but in many ways the project of aesthetic criticism is more vital and important then ever.
One major, and well noted impact of the Internet on Aesthetics is the creation of a multitude of parallel cultural universes that exist at the same time, everywhere and nowhere. Much of artistic criticism (and theories critical of the project of criticism) developed in a binary world of "approved" and "disapproved" Art.
To take two important early modern/pre modern examples, there is the French Academy. The French Academy was created in 1648 by Louis XIV, and its main purpose was to Judge "good" Art. Every year they would have a Salon and artists would enter their works and a jury would "judge" the Art.
This system was finally challenged in the 1870s by the French Impressionists when they established their own Salon des Refuses, a counter Salon consisting entirely of rejected and unsubmitted works of Art. Many of these Artists became some of the most succesful Artists of the 20th century, and it's easy to see how people looking at this example would draw the conclusion that the project of "judging" art is ridiculous.
The Impressionists and the Salon is an excellent example of the historically binary nature of Arts Criticism with Insider/Approved Art on one side and Outsider/Rejected art on the other. Given that framework, you can hardly blame more then a hundred years of Romantic and Post Modern critics for rejecting the critical project itself.
However, the times have changed, and cultural criticism no longer exists in a binary universe. Gone are the days when Art had to exist as an either/or with critical opinion. Instead, there are now a seemingly infinite number of cultural universes where critical standards are either entirely absent because the Audience is uninterested in the aesthetics of the art they are consuming OR where criticism is specific to one cultural universe and is unable to cross boundaries in the historical tradition of universally appreciated Art.
Criticism now plays a critical role in linking these parallel cultural universes and the impact of this linkage is to increase the potential Audience for any one Artist. It is the critic, acting in a traditional (Pitchfork Album review) or non-traditional (Tumblr blogger retumblring a music video) that in fact generates these parallel universes- not the Artists themselves, for without the distinct Audience, the Art would essentially not exist.
It's a sprawling, diverse and undisciplined group of voices to be sure which means that the role of any individual trying to grasp contemporary art aesthetics has a difficult to impossible task. However, should any one person gain the ability to recognize art that exists in one universe that could be embraced by a parallel universe and then act to make that actually happen, that person essentially has an alchemical process to transmute the lead of unappreciated sub-cultural artistic products to something that is capable of supporting an individual of business for eternity.
The key trait is the ability to recognize quality this among art with no present audience, it's the alchemy of taste.