Charlie Lee has worked for Coinbase over a year and he can't even convince his superiors to adopt Litecoin, what does that tell you.
It tells me they can't find a counterparty they trust enough to regularly supply them with enough litecoin to get that segment of their business running. Lee has openly admitted that they're still two years behind bitcoin, development-wise obviously this includes exchange infrastructure.
And yet a coin like Bitmark(https://bitcointalk.org/index.php?topic=660544.0) has managed to get an scrypt coin codebase going based off the latest version of Bitcoin in less than a month with one unfunded developer? Wow. 300 mil market cap sure bought a whole lot of nothing.
Why aren't Litecoin holders more angry at this point? Why hasn't there been a mutiny or something to save the coin?