Fencer: Yes, that's true. ISPs are obliged to keep their DNS lists updated and the only thing we can do for that is to broadcast the up to date information and "ask them" to accept it.

Yeah, but you can make your change the "right" way, or the "wrong" way. DNS records have a TTL (time to live). If I look at the current DNS record for brainking.com, the TTL is one day (which is a typical value). Now, if the TTL of brainking.com was one day before making a change, it means that it may take an day before everyone knows about the change. No ISP would be violating any RFC. The "right way" (that is, decrease the time it takes for everyone to notice) of making a DNS change is to first lower the TTL to a short period (say, 900 seconds), and do this more than a day in advance (a day because that's the old value of the TTL). That tells any name resolver that it should not keep an entry in its cache for more than 15 minutes. Then you make your DNS change, and you can set the TTL to one day again.

Now, obviously, I do not know how the DNS change was made, but judging from the reactions of the board, it seems that for about a day, people had problems with name resolving. Which seems to suggest a change to a record with a TTL of a day was made.