I agree with DeathAndTaxes on this one. It's not worth trying to limit hardware because it's improving all the time. By the end of this year Intel is expected to release their new Knights Corner 50-core CPU. That will be a good one for mining Litecoins, according to Artforz on btc-e. Are you going to try and stifle that one too?

Do you have any hopes of Litecoin ever becoming mainstream? It won't happen while 50% of the mining is done by botnets! That's why the Litecoin price is so low: nobody is going to put any serious money into a botnet currency.

A GPU miner is the best thing that could happen to LTC because botnets don't have GPUs. Let's leave Litecoin as it is and let's get mtrlt to release an open source version of his miner. I read that he spent only a few hours working on it so the Litecoin community should be able to buy it from him. I'm willing to donate 10 BTC towards this goal.