Some whiners think that ASICs are centralizing everything because they cannot buy one and make a buttload of coins.
But ASICs are the end of the line for hardware advances up until quantum computing, and even then it is so far away and it would be years before the return on the processing power of a quantum computer could match an ASIC.
As it is, several companies are popping up to provide ASIC chips. And they are looking to mass produce these things. Meaning a future of millions of cheap ASICs to be used primarily for mining bitcoins. N00bs will be able to buy an ASIC on Amazon and have it delivered in a few days to be plugged in and run with very little knowledge of mining. Unlike GPU mining or even CPU mining.
This may not be the case right now, but after a year or so there will be tons of ASICs out there. They may even be embedded in other electronics like TV boxes that pay for TV shows via bitcoins mined from your ASIC chip. All you pay is electricity costs. Or free cell phones with embedded ASIC to pay for your service, just make sure you keep it charged.
The only way to speed things up through hardware is just to have more ASICs. There is no next step for a long time.
Quantum Computers are not replacement for Classic Computers. Quantum Bits (qubits) operate on quantum states. Classical bits are represented as 0's and 1's, where qubits are represented as probabilities on a plane.
In otherwords, classical bits are represented as 0 or 1.
Quantum bits are represented as a|0> + b|1>.
The only difference in speed this makes is quantum computers are faster at doing quantum calculations (they can take shortcuts because of the fact that gates can manipulate qubits in an algebraic manner), but will not speed the process of doing hashes (something not necessarily algebraic)