Samsung appeared to announce a new mobile-phone OS today, but it didn't really. The mobile-phone giant sent out a press release and opened up a Web site today announcing Bada: a "new open platform" for mobile phones.

Bada is an extension of Samsung's long-time, proprietary feature-phone OS, according to company spokesman Kim Titus. That's the OS already running on popular phones such as the Samsung Rogue and Highlight.  Bada will initially appear on touch-screen Samsung phones in 2010. Titus added that Bada is "an extension of the GSM version of [Samsung's] operating system," which makes it look as though Bada may not be coming to Sprint and Verizon phones at all.

The Bada difference seems to be a native SDK for third-party developers to write applications directly for the phones. Up until now, third parties writing for feature phones have generally written for virtual machines on top of OSes, whether they're JAVA (Sprint, AT&T, T-Mobile) or BREW (Verizon, MetroPCS, Cricket.) Native apps have been one of the things differentiating smartphones from feature phones.

It looks like Bada may really blur that line. Samsung is preparing a native SDK and opening an app store. But many things are still unclear here. Feature phone OSes typically don't have robust memory and process management. Carriers tend to like their protected JAVA and BREW sandboxes (and revenue sources.)

We've asked Samsung many more questions about Bada, and we hope to have more details soon.