For a company with a history of keeping a tight lid on things, Microsoft Corp.’s decision to open its game-making platform to just about anybody is remarkably open-minded.

On Wednesday, the company said it would open up its Xbox Live online gaming service to developer wannabes as long as they used Microsoft’s XNA Game Studio software. Students among that group would be able to use the software for free. An annual subscription costs $99.

No, Microsoft hasn’t been hit by a withering bout of generosity. The idea is to boost traffic on Xbox Live and improve Microsoft’s profile in gaming, perhaps thwarting Sony and Nintendo’s advances on Xbox 360’s tenuous perch atop the gaming world. Nintendo fans already have a developer platform called WiiWare at their disposal.

Members of Microsoft’s XNA Creators Club will have first dibs on the offer this spring. They’ll also be able to develop games for the handheld Zune digital media player.

Microsoft believes this new program could double Xbox Live’s library to about 1,000 games by year’s end — just in time to entice new users for Christmas.

Sounds nice. And very generous. But what’s all this mean for everyone other than Microsoft?

Microsoft’s larger goal here, remember, is to make money, and more people tromping through Xbox Live should do that. Not only does opening the doors to developers, no matter their skill, give them a sandbox to play in they might not have had otherwise, but also more gamers probably will drop in as a result just to sniff around and see what’s on the stove cooking.

Of course, not everything will be worth tasting. Microsoft promises to police the service for appropriateness — whatever that means in Microsoft-ese — but quality is, as we say in the old country, a whole ‘nother kettle of fish. There’s just as much chance that Xbox Live, which already has an estimated 10 million members, becomes a dumping ground for garbage games as anything.

The good developers showing their wares may get called up to big-name game makers for their trouble. For them, Xbox Live holds potential as a resume-builder. And there may be a cost borne with that, though Microsoft hasn’t said what it is. The company was mum about pricing.

Still, it’s nice to know Microsoft is opening up a little, letting in some fresh air. If only it was this open-minded about everything else it does.