This also marks the point at which there are only 3M more Litecoin to go until the halving, which will see the Block reward fall from 25 Litecoin to 12.5 Litecoin. The halving is estimated to take someplace this august when 75% of the total Litecoin supply has been mined. At the current reward rate it takes ~70 days to mint 1M new Litecoin into circulation and after the halving this time will double to ~140.
It also means since Litecoin is deflationary we wont see the 70M milestone until approximately 1330 more days have passed, or sometime in mid 2022.
The final Litecoin is estimated to be mined sometime in 2142 according to the mathematics of the system, at this point 0.00000042 Litecoin will be the block reward.