The four strikes against Bitcoin:
First, Bitcoin mining is illegal. Do the research, bitcoin mining has all the legal elements of prize, chance, and consideration which makes it a lottery (see for example
http://www.blankrome.com/index.cfm?contentID=37&itemID=2300 ).The mining computers necessary for Bitcoin's ongoing operation are legally no different than networked slot machines under US State laws. Instead of "three cherries", your mining rig is trying to produce via a random process a "crypto hash" with a set number of continuous zeros. Hey, who cares that your winning computed crypto "hash" file is no better whatsoever in supporting Bitcoin holders / the blockchain than the trillon trillion other valid crypto hash files calculated and immediately tossed in the trash by losers. Be the first to calculate a valid crypto "hash" solution that ALSO coincidentally contains an irrelevant bunch of leading zeros and win a prize! Running a bitcoin mining operation in the US as an individual or business entity is an illegal lottery and its proceeds (mined Bitcoins) are subject to confiscation at any time by State Attorney Generals. Their press release could come at any time...
Second, current bitcoin mining exponential growth is unsustainable. The key graph at
https://blockchain.info/charts/hash-rate?timespan=all&showDataPoints=false&daysAverageString=1&show_header=true&scale=0&address shows that mining Bitcoin currently takes 300,000,000+ GHash / sec of computer power to keep this ponzi scheme going. Take for example a modern mining rig like a Butterfly Labs Monarch (
http://www.butterflylabs.com/monarch/ ) that costs $850 and uses 490W to produce 700 GH/sec of hash power for mining Bitcoins. If the entire Bitcoin mining ecosystem were Monarchs (which it isn't, it is a mix of equipment mostly less efficent and already obsolete compared to Monarchs), then there's 300,000,000 / 700 = 428,571 Monarchs out there at an installed infrastructure cost of 428,571 * 850 = $364 million dollars. This installed base of mining computers currently generate 25 Bitcoins / hit * 6 hits / hour * 24 hours / day = 3600 Bitcoins / day (currently worth $244 each at this writing, see
http://coinmarketcap.com ) for a total of $878,400 per day. If Bitcoin rates were roughly stable (ha!) this would be around $320 million per year. The average annual return on a mining rig is thus currently below its average cost so the current Bitcoin mining ASIC arms race and its exponential growth cannot be funded. That's why the super-mining union CEX.io has already pulled out:
http://www.coindesk.com/cloud-mining-suffers-hash-rate-plateaus/Third, Bitcoin mining is hugely wasteful and inefficent. There's only 6 * 24 * 365 = 52,560 winners per year in the Bitcoin lottery that injects new coins into the Bitcoin ecosystem (inflation!). With 500,000+ mining computers out there, 90+% of them will run all year and never get a hit, all the while sucking up at least 500,000 * 850 = 425,000 KWh per hour of electricity. At 15 cents per KWh average, the current Bitcoin system is burning at least $64,000 per hour / $560 million per year in electricity.
Finally, Bitcoin mining is unnecessary. Instead of 500,000+ competing "Proof of Work" (PoW) mining computers in the back room supporting Bitcoin behind the scenes, second-generation cooperative "Proof of Stake" (PoS) cryptocurrencies like the pioneering NXT can field the infrastructure necessary to support a vast population of coin holders with only a tiny network of a few hundred $35 10W Raspberry Pi 2 toy educational computers (
http://www.raspberrypi.org/raspberry-pi-2-on-sale/ ). Such PoS networks cooperate solely to support coin owners instead of primarily competing for miner prizes, making them far more cost-effective and efficent. Bitcoin is a dinosaur that cannot evolve to achieve this crucial advantage.
Bottom line: The current Bitcoin system has at least $364 million in sunk infrastructure costs and burns at least $560 million a year in power. The ONLY source of "income" to support this burden is (1) appreciation of the existing 13.8 million Bitcoins and (2) mining of 1.3 million new Bitcoins per year. Do the math - these numbers just don't add up to a stable system that's gonna work.
Four strikes, and Bitcoin's out.