Battery modifications required to get Boeing 787s flying again add 184.8 lbs. to each aircraft, Boeing's Alert Service Bulletin (ASB) detailing the upgrades says. Check out the 516-page ASB here.
Meanwhile, the carriers that experienced the two in-service battery issues--ANA and Japan Airlines, which also happen to have the most 787s (17 and 7, respectively)--aren't holding back with regard to keeping the public in the loop on resumption-of-flight progress.
Both are posting aircraft-specific status updates for their 787 fleets. As of today, ANA reported having two planes modified, eight in progress, and seven "under preparation." JAL said it had one modified, three underway, and three waiting in the wings.
ANA also is keeping a public log of daily test flights. Today's update (.pdf) reported two additional flights, boosting the total to seven since the first modified 787 flew Sunday.
Both the ANA and JAL websites have extensive information on the 787 situation, including airline-specific details and background on the grounding and subsequent investigation in general.