Normally I'd just place this in the One Stop Shop for gaming news but there may very well be people here who play both ArenaNet and Blizzard games and so this may be of vital importance to you.
The article on the hacking.
Seems email address, secret questions and 'some' personal details have been accessed for all players outside of China. Passwords were stolen however it supposedly 'encrypted' and not likely to be deciphered (It will be, like the Yahoo! addresses of June hack) so whilst Blizzard are pushing for players to alter their login details and cover their ***** I'd advise anyone here who uses the same email address and/or (shock horror) the same password with their guild wars accounts to quickly change them*
I'm not sure on how easy it will be changing passwords for Guild Wars with the accounts linked and all, but I'd recommend looking into it if you have ever played a Blizzard game.
*NCSoft accounts emails/passwords getting changed? - lol, you're screwed there