Launched Wednesday, Apple's new social media music service—Ping—has already pushed past one million signed-up users within its first 48 hours of existence. And according to a statement from Apple, the number represents more than one-third of those who have downloaded iTunes 10, the latest update to the company's popular music organization/playback/store-connecting software.

That hasn't stopped pundits from quickly weighing in on the new service, however. Regardless of how many users might be flocking to Apple's latest creation, a general consensus seems to be brewing that Ping, though promising, "kinda sucks," writes Business Insider's Jay Yarrow.

"It is fundamentally flawed because it doesn't interact with your iTunes music collection," he writes. "Without the ability to actually to actually tell our friends what we're listening to, Ping is a pretty useless service. Without the ability to listen to all our music through Ping, like we once did with Lala, the service is decidedly weak."

TechCrunch's Erick Schonfeld identifies another key issue with the service, in that Ping is entirely iTunes-dependent: In a world where social networks are Web-based communities that one can interact with and access from any location under the sun, Ping requires the software in order to work. There's simply no way to access or update any part of Ping without the iTunes dependency.

"And Ping doesn't communicate with any other social networks," writes Schonfeld. "I can't see people's iTunes Pings in Twitter, Facebook, or anywhere else. While Ping does make iTunes itself more social, the problem is that I don't live in iTunes. It is a store. I go in to buy stuff and get out as fast as I can."

To its credit, Apple did initially launch Ping with a hook into Facebook Connect as a means for letting a user find new friends on the service. However, the feature soon died a silent death at the hands of the company, allegedly due to Facebook denying Apple the right to use its APIs.

While the ability to dial into Facebook is normally a free feature for any developer to integrate, those expecting to push a large number of queries over to Facebook's servers are required to get permission prior to tapping into the site's directory.

Although Ping's one-million user count is an impressive statistic on paper, it's not one that's ultimately unheard of in the social music market. Rival service last.fm saw approximately one million new user accounts generated soon after the service was integrated into Microsoft's Xbox Live platform.

And with 40 million users hitting up last.fm on a monthly basis—which, itself, is but a single entity amongst a sea of social music service online—Apple has a bit of a way to go before it carves out a social foothold.