Diablo – How to change the “Breaking News” region in Diablo 3

You can change skills whenever you want, but there are currently two penalties:

There's a small cool-down in which you won't be able to use the new skill, which makes swapping skills frequently in combat disadvantageous...

...And swapping skills will cause you to lose the "Nephalem Valor" buff that characters over level 60 get from killing elite monsters, which increases your magic find, causes boss monsters to drop additional items, and, since paragon levels were added in patch 1.0.4, also gives bonus experience.

See also the question on Nephalem Valor

Diablo III's regions affect a number of things in game:

• Your selected region affects which server farm you connect to. The Americas region's servers are located in the USA, Europe's are (obviously) in Europe, and Asia's servers are in Korea. Australian and NZ players will be assigned to the The Americas region by default, and hence the USA server farm. There are no South-East Asian (Singapore) servers for Diablo III.

• The Real Money Auction House (RMAH) is region locked - the only RMAHs you have access to are those for the region your Country of Residence resides in. However, you may still have access to multiple RMAHs, as RMAHs are also divided by currency. This page lists the RMAHs you can have access to depending upon your Country of Residence. To use Australia as the example, the USD RMAH will have more items because of the US's larger player population, but the AUD RMAH will not have any currency conversion fees (source). These currency-based RMAHs are separate, i.e. an item on the USD RMAH will not appear on any other currency's RMAH, even those in the same region.

• The Gold Auction House is not locked within a region, but is region-specific, i.e. the European Gold Auction House cannot be accessed to provide items for characters in the Americas region.

• Players and items cannot be transferred across regions. Any item you buy on a RMAH or Gold Auction house cannot be transferred to a character in a different region.

Note that which version of the game you buy does not affect which region you're assigned to at all, i.e. buying a UK version of the game and playing in the USA or Australia will not mandate or even default to the Europe region. The default region selection is based off your Country of Residence in your Battle.Net account's settings.