84 million coins should be enough for an internet currency. Currency, not comodity, as Bitcoin tends to be. People could use it on SilkRoad, Alpaca Socks and other websites.
One argument for it's success would be that once bitcoin takes off, many will look at it as an opportunity of buying lots of coins cheaply, and thus likely starting a rally. But if will have no economy, and will be purely speculative, it will soon die as the rest of alternate chains.
If Litecoin is a scam coin, it can not survive till now and have a capitalization which is high like this. They have a really good team to go long way