Steve Jobs’ troops are in town

5,000 Apple developers have descended on San Francisco to get this year’s marching orders

In sheer numbers — and security measures — Apple’s WWDC 2010 can’t compete with “Israel in the Gardens,” the annual festival for Bay Area Jews that stationed metal-detecting guards at every entrance of San Francisco’s lovely Yerba Buena Gardens Sunday and drew a crowd of nearly 20,000.

But in the world of Apple (AAPL), the Worldwide Developers Conference that begins Monday with Steve Jobs’ keynote in the Moscone West auditorium — just across the street from the gardens — is a very big deal.

It’s the company’s premier technical conference, and this year’s edition sold out in a record eight days as 5,000 developers shelled out $1,595 (not counting travel, lodging, and food) for a chance to hear — from the co-founder himself — what Apple has in store for them.

The bloggers, the tech press, the international TV crews with their satellite trucks will queue up Monday morning to see the new iPhone and whatever other tricks Jobs has up his sleeve. And then they will be politely but firmly shown the door.

That’s when the real business of WWDC begins — under nondisclosure (as iPhone Savior notes, attendees are warned that anything they learn after the keynote is Apple Confidential Information, disclosure of which is strictly prohibited, even in blogs). The meat of the conference comes in technical sessions and labs on everything from “Mastering Xcode for iPhone OS Development” to “Advanced Objective-C and Garbage Collection Techniques” led by 1,000 engineers that Apple has shipped up from Cupertino.

As the banners draped across the lobby of the conference center make clear (see below), this event is for the people who created 200,000 iPhone apps and 5,000 iPad apps. It’s those applications and the software ecosystem that supports them that have given Apple what looks — at least for now — like a huge lead over Google (GOOG), Nokia (NOK), Research in Motion (RIMM), Microsoft (MSFT), and anybody else who wants a piece of the market for advanced smartphones and tablet computers.

There’s a lot for the developers to soak in. Multitasking in iPhone 4.0. The new iAd advertising platform. The new social gaming tools. And the new opportunities — especially in print and video — that the iPad’s larger canvas provides.

What Jobs and his engineers are going to try to do is fire up the developers, convince them that there is still lots of money on the table, and leave them armed with the tools to write the next 200,000 apps.

The hope is that they will write them for Apple’s platforms, and not for someone else’s.

We’ll be in the press scrum Monday morning. The doors open at 7 a.m. PDT (10 a.m. EDT), and the keynote begins at 10 a.m. PDT (1 p.m. EDT). Tune in here for our live blog.