I guess the question is how soon you need a camera? If you already preordered, then you should have yours Nov. 24 which is rapidly approaching. Is that soon enough for you? Do you need a powerful, high performance prosumer mirrorless camera? If so, then I suggest the wait for the GH2 will be worth it for you.
Start with those, and expand as you desire. Also, don't forget, with adapters, you can adapt other lenses (e.g., Canon, Nikon, Leica) to your GH2. You can also use Olympus and other MFT (Micro Four Thirds) and with adapter FT (Four Thirds) lenses. I would start with the Panny 20mm though. Good luck.