But it's also because we need a payment method that our customers cannot reverse is important to us. Bigger international customers will do a wire, but there's a lot of smaller guys and Bitcoin is a bit easier than Western Union sometimes.
But for Overstock and Dell? It's pure marketing.
User may not want it now because they're not familiar with the technology behind it or perceive it as being an uncommon and difficult/unsafe method to use.
But once they see bitcoin as an available payment option on all their favorite retail sites, they would be interested to at least learn more about it.
I hate when my banker says this to me about online banking.
If it really was noise, http://i.imgur.com/XJs4V74.png wouldn't show a relatively smooth exponential-looking curve.
For sake of argument, let's say that coinbase keeps 100 small, hot wallets around. Every time coinbase rearranges funds in their wallets, they could create between 1 and infinity transactions. If, on average, they rearrange funds daily in such a way that 25 transactions occurs, they would account for 50% of your increase alone.
Given that all exchanges and processors routinely shuffle funds around, and every move is recorded as a transaction, you need exchanges (in total) to make 55 more transactions/day to make up your superduper exponential growth.
20K increase in transactions in bitcoin is no increase in transactions.