The Panasonic GH2 is NOW in stock at B&H Photo and at Amazon, below are the direct links. Also, my 3 tested and recommended SDHC cards for the 42Mbps GH2 patch/hack.
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Panasonic GH2 available in two lens flavors at Amazon. Only 1 left with the HD 14mm-140mm kit!
Also available here with the 14mm-42mm Panasonic GH2 at B&HPhoto.com
My recommended SDHC memory cards that work well with the 42Mbps GH2 Patch. I suggest the 16 Gig cards because we only get about 48 minutes of footage at 1080/24p. I also tested my cards with the 720/60p 42Mbps patch and all 3 cards work just great for in-camera playback and recording with the Panasonic 14mm-140mm lens.
My testing method was to shoot 10 minutes continuous footage at 1080/24p and then 10 minutes continuous footage at 720/60p with the 42Mbps patch installed.