Hopefully none of them gets an extreme advantage in technology, otherwise centralisation is inevitable.
Centralisation is already happening as we speak.
At the current rate, by the end of the year the majority of the hashrate will come from a dozen or more large corporations running multiple data centres around the globe. They will probably go at each other for a period until a few drop off, and the equilibrium will probably be spread across about 5 or 6 major corporations throughout 2015 - 2016.
this is wrong...
Why are you wrong here is why:
as of today the majority of miners are in the hands of less then 10 companies.
In Fact KNC + CEX +BFL + BITMAINTECH +ASICMINER + SPONDOOLIES = more then 51% of the gear in data centers. They mine for their selves or rent their hash out.
Home miners with serious fire power no longer exist.
In order to have a big in house setup. you need to rent a warehouse . what homeowner can give 10k watts in their house for mining alone.
and that comes to 3 sp30's which is a drop in the bucket 13.5th is not much against 200ph