WhassApp is the standard in Mexico. It replaced Windows Live (MSN) Messenger after they killed it by trying to make everybody switching to Skype and the interest of the people shifted to mobile.
MSN had 350 million active users a few years ago. And they just pissed it into oblivion. MSN had Skype feature set before Skype, but did nothing to publicize it.
And also, think - MSN had everyone's friends info, as well as frequency of contact and so on. It would have been a perfect way to launch a real social network. MSN fumbled that too.
AFAICT it's become the standard in italy too. People use it way more than facebook now, judging by my contacts (and I don't even use it, I just see a bunch of people doing it).
