Hi Dpm,
Yes, support for iPhone 3GS is right around the corner. The last update I got from the guys over at Flexispy, was that they are roughly 1-2 weeks away from having full support for iPhones using v3.0. In fact, they also have a few surprises to announce with their next release, that you will definitely like.
If you want to get notified when their update is released, sign up for my iPhone spy newsletter at
http://www.iphonespy.com and you'll get notified before you read about it anywhere else, or you can keep checking Flexispy's website at
http://www.flexispysoftware.com .
Let me know if you need anything else.
SPG