[yebyen]

It is just different enough to be separately viable at the same time; the blockchains are incompatible down to the hash level. Second it rewards people with lots of hardware and not specialized hardware, which is where Bitcoin is going crazy right now, because a few players have got their hands on something that the rest of the network won't have for some weeks or months to come (ASIC).

ASIC miners for bitcoin are not viable for litecoin because the litecoin scrypt hashing process is memory dependent, not CPU-bound like bitcoin / SHA256. My information comes not from any technical expertise but from interpreting what I'm told by people who have done more research than me.

Maybe someone could explain better?

[nwh]

The central premise for Litecoin using scrypt was that it was not able to be mined on GPUs, this was quickly proved wrong and the statement retracted. There's no technical advancement in LTC, it's just a weaker bitcoin clone.

[yebyen]

GPUs these days have alongside their massive collections of ALUs, large tracts of fast local memory. That's why they are viable for LiteCoin mining.

ASIC implementations for Bitcoin will be based on SHA256, built with not a lot of internal memory that can be accessed without traveling across another bus. Those implementations will not work with LiteCoin or scrypt, which is memory bound. GPUs have lots of memory.

It's no technical advancement over Bitcoin, I agree, but it is gaining acceptance (the prices have maintained parity with Bitcoin growth) and it seems that your current investment in LiteCoin mining will remain relevant for longer than old Bitcoin hardware, just because ASIC developers working on Bitcoin problem all see LiteCoin as just a weaker Bitcoin clone.

That's not an argument against LiteCoin.