This same discussion happen in the i760 rumor thread on 4-7-2007, here is my post about it:

http://pdaphonehome.com/forums/617050-post958.html

Read point #4. I read the information from 3GSM when it was announced, but it's not going to be until later this year before 4GB MicroSD cards are out, but yes they are coming.

So read my post, as it seems that MicroSD supports SDHC in it's standard.

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-Michael
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