Why not start them both at the same time? XD; It shouldn't get you off track or anything. When Diamond and Pearl came out, I bought both of them on the release day and played them both at the same time (not exactly the same time, but you know what I mean). You will probably get better answers if you ask in the respective places, though. For Platinum, try asking in the 4th gen Q&A thread, and for Black, in the Black and White forum's Q&A thread. Trust me, you will get better and quicker answers that way. :) Both are fantastic games though, and I'm sure you will enjoy them, whichever order you decide to play!
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