According to The iPhone Blog the upcoming release of iPhone 3.1 OS includes support for using the next/prev track controls on Blue Tooth head sets.
iPhone OS 3.0 introduced support for stereo BT head sets including partial support for the controls (volume and play/pause), but curiously no support for skipping tracks. 3.1 will remedy that thankfully.
There are other features and improvements in 3.1, for example, you will be able to paste into the phones keypad screen (automatically transposing alpha-numerics phone numbers into digits) and some updates to 3GS specific functionality.
Unfortunately, there isn't any mention yet whether Apple has identified the root causes of 3.0's battery consumption and heat issues.
3.1 beta 2 released this week, expect several more betas before the final product is released.