I think litecoin even has the potential to replace bitcoin. Dropping the BTC value dramaticaly.
It solves one of the biggest issues technically and emotionally.
Shorter block times somewhat increase the time it takes for a transaction to be verified decently.
This also speeds up the adjusting of the difficulty, something that i still see as a potential problem for bitcoin.
More user-friendly GUI.
Announced before release, 'no' premined coins, no small group of early adopters.
CPU mining makes it slightly more fair as the hashrate doesn't increase as extreme with newer CPU's as with GPU's.
(I do see this as a temporary situation, at some point GPU's will be able to work scrypt)
The argument that LTC is to BTC as Silver is to Gold is complete nonsense imo. Why? Because there are more LTC in the end?
There is less Silver in the world then Gold currently, the only reason Silver is Gold for the poor is because poor can't even afford one Oz. of Gold. There's no technical reason, it's convenience and price related.
Since BTC are extremely dividable this makes no sense at all. If you're poor and want to buy BTC @ $2.000,00/BTC then just buy 0.0005 BTC for a buck. Try doing that with Gold, find somebody to sell you 0.0005 Oz. of Gold
After that, find somebody to accept it or buy it back!
LTC improves on BTC imho.
BTC has the advantage of being already established somewhat, there are applications for it and there's an active economy.