disclaimer: I don't have a dog in this race, I have other ways to make or lose money.
i really have no idea why people would think this bitcoin is any safer than the multitude of currencies we have going already.
I take it they conclude this from the inability of monetary authorities to manipulate this currency.
who determines it's value against the base currency? is it quoted against the USD?
It has an exchange ratio with the USD, and presumably any other currency you care to exchange.
The exchange ratio determines the value of a bitcoin in relation to a USD. Normal rules of supply and demand.
who controls how many bitcoins are in circulation?
The software has a deterministic algorithm for the number of bitcoins produced. There is a finite number of bitcoins allowable. The rate at which they can be produced is predetermined and slows predictably over time. The holders of bitcoins determine how much is in "circulation" by transacting or not.
if you invest in this, don't come back here seeking sympathy when it fails. we WILL laugh at you.
You cannot earn interest on your bitcoins, so it is not an investment which defers current consumption for greater future consumption.
You cannot earn dividends from your bitcoins, so it is not an investment which generates a capital return. Bitcoins cannot provide any cash flow to the holder by virtue of owning them.
So it is not an investment, it is a store of value which has the property of increasing it's exchange ratio to other objects over time. Therefore holding bitcoins for future gain is pure speculation.
of ffs, i just skimmed the article. they punt decimal places as an advantage. someone should tell them that banks are willing to trade to 4 decimal places with clients that are big enough.
Because the total number of bitcoins is predetermined and finite, bitcoins are a deflationary currency, ie. the exhange ratio of a bitcoin is generally increasing in respect of other objects. So over time the denomination of a bitcoin becomes unusably large in general trade, so the denomination must be reduced, for which purpose a bitcoin has 8 decimal points.
This works the opposite to fiat currencies, like the dollar, where the original fractional denominations are now worthless and unused, and the valuation moves to the left of the decimal point. (a 1900 penny is now ~= 1$)