From Nikon-Labs.de via Google Translate:
"In recent days, rumors circulate again on new bolts from the house of Nikon through the web. It will be a SB-500 SB-700 and act. Both flashes to be later this year. Technical data or more precise details are not yet known. The SB-500 will probably be the SB-400 to replace. The SB-700 flash, the SB-600 so far."
No source for the rumor mentioned, could be pure speculation.
Source: nikon-labs.de on 1/16/2009.
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