That’s roughly double the number that were available when the store opened just over two weeks ago (on July 11, the same day the iPhone 3G went on sale), and includes popular games like Texas Hold’em and Crash Bandicoot, business tools like Bloomberg News and Salesforce Mobile, and social networking programs like Facebook, MySpace and AIM. Roughly 20% of the apps are free; 90% cost $10 or less. Most also work on the iPod touch.

Many consider this flood of software to be a bigger deal than the phone itself. Among smartphones, only the RIM (RIMM) Blackberry has created a comparable platform for so-called third-party programs (see its application store here), but because the Blackberry lacks a touch screen and accelerometer, its apps don’t compare with the iPhone’s in terms of features and ease of use. [Several readers note that Microsoft’s (MSFT) Windows Mobile and the Palm (PALM) OS also provide rich software platforms. You can view their offerings here and here, respectively.]

How you feel about Apple’s App Store seems to depend on what side of the virtual counter you stand.

MG Siegler, speaking for many App Store customers, declared it “simply sublime” in his Venture Beat column and described it as a new paradigm that would transform Apple as a company. “With each passing day I’m finding myself becoming addicted to it in the same way I was once addicted to the iTunes music store.” (link)

On the developer side, however, tempers are becoming increasingly frayed. The programmers who raced to create applications — hoping to be the first in their particular category — complain that Apple isn’t approving their submissions fast enough and that when their apps do get OK’d, they’re not getting promoted on the store’s New, What’s Hot or Staff Favorites sections or updated quickly enough. New versions sit in the queue at Apple for up to a week, leaving users to wrestle with bugs that have already been fixed. “If an update does make it into the store,” writes David Chartier in an Ars Technica article that summarizes the litany of developer complaints, “iTunes isn’t always listing the correct version. NetNewsWire, for example, is actually at version 1.0.7, but the App Store says only 1.0.1.”

But the programmers’ biggest gripe is the gag order imposed by Apple’s so-called NDA (nondisclosure agreement), which prevents developers from talking to the press, to the public and even among themselves about their programs and the SDK (software developers kit) they use to write them.

This can have real repercussions. Erica Sadun, author of “The iPhone Developers Cookbook,” (Addison-Wesley), has had to delay publication rather than risk running afoul of Apple’s legal team.  “[My publisher has] advance orders,” she told Ars Technica, “they have commitments.”

A “very polite petition” asking Apple to lift the NDA had drawn a couple hundred signatures as of Monday night. By then, a Web site called “[expletive deleted] NDA,” which keeps track of every time that phrase is uttered on Twitter, had collected 15,000 hits.

On Sunday, July 13, Apple (AAPL) issued a press release announcing that 10 million apps had been downloaded from the App Store in its first three days; by July 21, that number had risen to 25 million.

“The App Store is a grand slam,” said Steve Jobs. “Developers have created some extraordinary applications, and the App Store can wirelessly deliver them to every iPhone and iPod touch user instantly.”

Apple has not yet marked the 1,000 application milestone — or responded publicly to the developer complaints.