Someone on Woot got their GTab today. Says its firmware is 3389, one step below 3558. So everyone should be good to go with modding it. One of the XDA mods said to go ahead and do the OVA update to 3558 first. Here
Still waiting on mine. Looks like I am in the second round of shipments. May not get it till end of week. Almost tempted to get the one from Tiger Direct and get it by tuesday.