One of these, right?
That's not a debit card. It's a prepaid card. Presumably it's been preloaded with some amount of money. Maybe they'll refill it from your Coinbase account if you use it. Maybe not.  Here's the FAQ from the card issuer. There's a site where you can register the card, then read your balance. It may be that the people behind the Bitcoin scheme have already done that, and they're monitoring balances and refilling. Or not.

Incidentally, after one year, you'll be charged 1000 yen for that card.

They may not even know when that card is used.

What could possibly go wrong?

3  blocks to go, and it looks like the next difficulty adjustment will be about +1%.

It's a relatively obvious analysis. Most of the info is from "blockchain.info". There's no sign that the author has any inside information about the operation of big mining farms, or what they're paying for hardware.

We had a drop in the hash rate for about two weeks. That's why it's taking slightly longer to get the required number of blocks. Then the hash rate went way up. No idea why. Maybe one of the big mining farms was doing an equipment upgrade and shut down for the changeout.  The difficulty adjustment tomorrow will probably be 1-2%, much smaller than last time.

There was a drop that lasted for several weeks. That's not just noise from the rate at which blocks are found.

It's possible that some big hashing center was doing an upgrade, and they were shut down during the upgrade.

There's discussion in China of reducing exchange controls on yuan. But if China reduces exchange controls, people with yuan in China won't need Bitcoin. The China bubble was because, for a brief period, Bitcoin was a safe, legal, remote way to convert yuan into dollars or euros. The previous legal approach was to get all your relatives to travel to Hong Kong every three months, loaded up with the legal maximum of yuan notes. This is a pain if you're not in Shenzhen.

If you have no idea what the above is about, you probably were screwed by the collapse of Bitcoin prices.

If Bitcoin ever gets enough usage that the 7 TPS transaction rate is reached, fees will probably go up.  Miners have no incentive to adopt a larger block size, and every incentive to raise fees if they can.

Agreed.

How big was the dump six hours ago?

Right now, there is a huge dump of 13780 bitcoins on Bitstamp, offered at $300. That's the current price.

Bitcoin transaction volume in USD.

Take a look at the last year of Bitcoin transaction volume in USD. There was the China bubble, a big spike and decline, and then the Mt. Gox manipulation/collapse, a huge but very brief spike. Then the transaction volume in USD settled down. For the last six months, it's been surprisingly flat.

What this means isn't entirely clear, but it does indicate that Bitcoin usage is not increasing.

Suddenly, in the last two days, the hash rate went way up. Somebody just brought substantial new mining capacity on line. Looks like the difficulty will not go down.

Any idea who has the new big mining farm?

You're the mark. This is a zero-sum game, and it needs a steady supply of suckers like you. The Bitcoin world thanks you.

Very good point. The last bubble, from about $120 to $1100, was driven by the use of Bitcoin in China to get around China's exchange controls. Once the People's Bank of China stopped that, the price started back down.

No, there are people on localbitcoins trying to sell Bitcoins above $400. Buy prices are as low as $289.

Those are just bids and asks that are far from the market, like the ones you see on any exchange.

Another $15 and we're below $300.

Right. They just need to automatically change their price once a minute.

The basic service Coinbase provides is that they'll guarantee a Bitcoin buy price to a merchant for a minute or two. This removes market risk from the merchant.

Way below that already. 320 on BTCE right now.

Those "walls" always move with the price.

They're betting that Bitcoin will go down. That's been a good bet for the last 9 months.