Avatar added $15 million domestically
Titanic held weekly domestic totals above $30 million through week 9 and above $20 million through week 14. Dark Knight was under $30 million in week 5 and under $20 million in week 6.
If Avatar can hold as well as did between weeks 3 and week 4 into the later weeks then
Week 5 box office $64 million [Expect $68 million, but had long weekend]
Week 6 box office $50 million
Week 7 box office $40 million
Week 8 box office $30 million
Adding that to the total likely after today (Thursday another $5 million to end week 4) would be $450 million + 184 million or $634 million. Titanic would be passed at the end of week 7. The above weekly decline rate would target about $700 million domestically.
Titanic defied box office weekly declines by making more money in week 5 than it did in week 4 and then massively slowing its weekly declines.
If this weekend domestic numbers hold to about $40 million then that would indicate tracking to the $700 million target. If it held above $40 million then it would indicate Avatar was biasing towards Titanic like box office longevity. Avatar would likely then hold above $20 million past week 9 and towards week 15.
My adjusted estimate is $450 million domestically and $0.99 billion right now for 1.44 billion.
My guess going forward is another $250 million domestic and $800 million overseas.
UPDATE: After weekend up to $1.615 billion. Expect $85 million for Tuesday, Wednesday and Thursday (foreign was not counted for Monday yet). For $1.7 billion by the end of week 5.
$350-360 million added in Week 5
Week 6 - $260 million est
Week 7 - $200 million est
Week 8 - $140 million est
END UPDATE
For a $2.55 billion world target. Worst case seems to be now another $150 million domestic and $500 million overseas. For a $2.1 billion world total.