I predict 0.002btc/gh in the future. Twice what a gen3 asicminer will cost.
Also the value will surely go way down due to the havelock bitcoin difficulty derivative (where you can rent gh or speculate against mining).
Speculators will be more than happy to sell you gh on havelock for much less than cex.io is charging. Reason being that speculators are willing to take a much lower profit (still more profitable than mining).
Cex.io is making bank off noobs and their hashrate is evidence of that.
So where besides CEX can a technically challenged noob like me participate in mining?
Why do you want to participate in mining?
1) "To make money" - Answer: Don't mine Bitcoin.
2) "Because it's fun / interesting" - Answer: Learn how to set up your own mining machine (for scrypt-altcoins ideally).
3) "To help protect the network" - Answer: Cex.io already has the hardware, you're just buying a mining contract from some other trader and aren't adding to the protection of the network.
+1
Mining isn't something that anyone with a big stack of cash can throw money at and get more money in return. To profit by mining you need to know what your doing which takes time/experience. I've been watching/participating in the mining game for over a year now and I still expect to NOT make a profit.
If you are a noob and are driven on making a profit I would suggest considering investing in asicminer. They know what they are doing (having invented asics) and can obtain hardware for less than the average joe can. Also with gen3 sales they will be seeing profit much more than mining alone.
If you are a noob/pro who thinks they know the mining game you can speculate with the bitcoin difficulty derivative. It's basically cex.io but when difficulty changes, the left over btc is given back to speculators (since divs are now lower due to difficulty thus requiring less btc to pay them)
Since your question was how can I participate in mining I assume profit doesn't matter. That being said I would just buy a ~$60 miner (bitfury/bitmain) so you can mine without a huge risk since any money you spend on a miner will likely never come back.