There is a possibility that nothing significant happens when mtgox implement LTC.
The only real reason for the sudden jump is a lack of supply due to large purchases and very low sales.
Some say that people will buy LTC to take out money from mtgox.
Also can buy BTC right now and sell on other exchangers with some loss. They will have the same loss if they try to sell LTC on other exchanges. there will be a small number of those who will buy LTC at a low price and be able to make sales to other exchange offices with profit.
If LTC  jump on MtGox will this be the case in all other exchanges?...or will make a huge difference, more than the BTC?