One thing to keep in mind now is that, for the first time, there is a fundamental difference in the organization of the mining between BTC and LTC.
BTC will continue to oligopolize, and be dominated, likely, by a few players like ASICminer which have the capacity and the cash flow to maintain their market share regardless of network hash rate, and thus induce increases beyond those caused by new hardware coming on line. This will likely drive all the GPU and FPGA based miners out of active mining. It will also mean that people that are now buying fixed hash power, regardless of the absolute amount, are going to be disenfranchised in relative terms in BTC.
For the reasons everyone knows - primarily those associated with the work algorithm difference - LTC will remain more decentralized.
I have my own ideas of what this is going to mean in relative and absolute values of the two, but so does everybody else have their ideas, so I'm not going to bore anyone with mine.
I also see bitcoin becoming an oligarchy. I find it interesting that such a seemingly small detail such as differences in the computational characteristics between the two hashing algorithms could have such a big impact on the organization of the litecoin and bitcoin mining networks. I have seen some threads recently proposing to change the bitcoin hashing algorithm because of the issues you raise, but if ASICs already control most of the network, I wonder if it may be too late.