Just speaking my thoughts here...
All BTC, LTC, PPC, etc price is valued at the price the adopters, miners, investors, speculators, traders etc deem the crypto-currency to be valued at. Having said that the foundation of the Blockchain and Satoshi's ideas and work to create a decentralised money system has attracted a wide spectrum of people so far who believe in the idea and the founding principals of such a monetary system. As word spreads other like minded people will join in and make some form of investment or interaction with the currency and this will only increase the value of the currency (baring a few extreme malicious investments).
If a coin is "Easy" to mine... then the value of the coin will be proportionally lower as there are a lot of people capable of mining with some serious Hashing, and there are a lot of computers out there that can/are used for mining (I know its still small compared with ALL the computers out there... but of those interested in crypto-currency, there are proportionally more people mining than if everyone was interested in crypto-currencies) ... but sorry got sidetracked... basically people will and do "Pump and Dump" coins... mine a coin and sell for one with higher $ value
If a coin can be used to trade for both $, £, etc.... then "financial investors" are interested, individuals who may speculate on the value of the coins can then buy them, alternatively people can invest the coins to try and accumulate more, for example I know of someone who has written a bot to trade BTC and USD ($) on MtGox, and he has set up an investment fund to allow others to invest in his market expertise and faith in his bot and calculations and you get paid in BTC weekly for your investment etc...
Also by trading from the coin to another currency this is the outsource for the "miners" to convert their mined coins back into £ or $ or whatever to pay their electricity bills and hardware expenses etc...
If a coin can be used to buy goods etc... then the coin reaches more of the general public, and potentially more of them will buy some coins or mine etc... but it is important to remember I feel that these people interested in the coin will probably not read all the papers on the coins, blockchain, etc but will only really become aware of the currency once they go to purchase something and need the coins.
All this said .. one can not avoid the fact that looking through BTC charts
http://bitcoincharts.com/charts/mtgoxUSD#ig12-hourzczsg2010-12-01zeg2011-08-31ztgSzm1g10zm2g25zv that the sudden rise in the value of BTC was due to being able to use BTC to buy actual goods that you may not be able to get elsewhere.... a prime market for a new currency
... but this showed both the value of the currency to the people who had coins... as now they could potentially cash out at a higher than initial investment, and to the people also wanting to purchase such goods as now they needed to get hold of some coins. Personally it is still a rather tentative area for me in BTC as i feel that BTC needs to be backed by alternative sources, ie spreading the risk in investors and buyers.... for example say we all used our BTC to buy potatoes, and only using BTC could you buy potatoes and that was all you could buy with BTC then I think you would find a number of "investment" funds where you could get paid small amounts of potatoes for your initial investment... you would find a number of potato scams
and gambling sites... might even be able to buy a golden or silver potatoe!! .... But what happens when suddenly there is the potato famine as in 1845, and scientists discover that potatoes actually cause you to spontaneously combust and all the governments across the world unite to outlaw all potatoes... extreme i know but for the sake of an interesting hypothetical... this would make the BTC and potatoes worthless except for a minority of die hard potato fans as no one would have the "NEED" to buy BTC (or potatoes)
There are a few ways it could go though... say the people mining the coins were able to pay their electricity bills using the coins they mined.... and they were able to buy all the hardware using the coins they mined... then the miner would be able to accumulate wealth in the coins and not need to sell all the coins.. agreed with mining if this was the case then everybody would be doing it!! but that is the beauty of the "difficulty" and the limit on the number of coins in existence etc etc.. but my point being that if there is a way for a business to cover their overheads with the crypto-currency then there is a greater chance of more business using BTC and other crypto-currencies.
Sites like
http://www.bitmit.net/en/recent personally I think are a real step forward for the currency as it allows people to get their hands on some of the currency by selling items they have, or for small businesses and individuals (like miners) to buy equipment using BTC.... I think that this is such an important part to the Coins stability in value that I have been working on a PPC Auction site... but it still a work in progress...
Just in speaking to my friends about BTC and other crypto-currencies, I have found that there has to be things the individual can buy with the currency... more than just trading back to $ etc for them to feel secure or interested in buying any coins... or if they are a VERY early adopter then they can be convinced to mine
... but maybe it is a reflection of the people I speak to.. but they are all interested but none are yet to buy any, one other friend mines...
But what is the value of LTC based upon? the price of BTC right?? and same with PPC and all the other currencies out there... for now it is only really BTC that has a wide pool of people who will buy the coins in order to buy other material goods with them. I do not know of a LTC auction site?? or something other than a ponzi scam or gambling site related to LTC?? no company selling gold, silver or coffee beans (
http://bitbrew.net) for LTC.. yet... but i think the market is there for such companies in LTC and even PPC in due course... and this will only help to strengthen the value of the currency....
If however a country say like Finland
or say a struggling financial country like Greece looked to invest in BTC or LTC etc and use it as the nations monetary system then it just gets interesting for all of us with any coins
as number of people on the network would reach unpressidented highs and there would be no turning back for the currency and the decentralised monetary system.. well that's what i feel.
TL;DR Just make more sites where you can buy and sell genuine items for all crypto-currencies,
If you could only buy oil for LTC, then LTC would be valued higher than BTC i think you would find