Some have it completely wrong, Microsoft.... Some have it completely right, Sony... Some have it somewhere in the middle, Nintendo. What am I referring to? It is how the three major console manufacturers handle the usage of their "points" to buy DLC content.
Microsoft forces users to create some sort of mathematical equation to sort out how to convert currency into Microsoft Points. And what happens if you have 750 Microsoft Points and need 50 more? You have to buy them via pre-paid cards or in set amounts that Microsoft sells them in online. Not a friendly system and not a good way to treat their customers.
Sony, on the other hand, actually gets the DLC concept. They use actual currency--so you know what you are spending. In addition, you are allowed to combine any credit you have and pay the difference via a credit card. So no fear about being forced to buy large chunks of Sony Points. Despite the highest priced console, Sony understands how to make buying DLC easy for the consumer.
Finally, we get to Nintendo. Nintendo offers a solution somewhere between Microsoft and Sony. The Wii uses Wii Points, now known as Nintendo Points, to buy content. 100 Wii points equals a dollar. The great part about the system is that Nintendo has a store available on the new Nintendo DSi console. So if you are eager to go spend some of those points that you have linked to your Wii console, which is linked to your Club Nintendo Account, better get ready to shell out more cash. Nintendo forces users to choose how to redeem their points. If you redeem them on the Wii, you can only use the points on that single Wii console. If you choose to redeem them on the Nintendo DSi, you are locked to only getting content for the DSi.
Why Nintendo can't have a single login and share the "virtual currency" is a complete mystery and further proof how out of touch NIntendo is with the technology for the online space. Buyers beware when dealing with DLC for the Wii, DSi, and the 360. At least Sony has your back on this one though.