From the WhatsApp blog:
...we're happy to announce that WhatsApp will no longer charge subscription fees. For many years, we've asked some people to pay a fee for using WhatsApp after their first year. As we've grown, we've found that this approach hasn't worked well. Many WhatsApp users don't have a debit or credit card number and they worried they'd lose access to their friends and family after their first year. So over the next several weeks, we'll remove fees from the different versions of our app and WhatsApp will no longer charge you for our service.
Naturally, people might wonder how we plan to keep WhatsApp running without subscription fees and if today's announcement means we're introducing third-party ads. The answer is no. Starting this year, we will test tools that allow you to use WhatsApp to communicate with businesses and organizations that you want to hear from. That could mean communicating with your bank about whether a recent transaction was fraudulent, or with an airline about a delayed flight. We all get these messages elsewhere today – through text messages and phone calls – so we want to test new tools to make this easier to do on WhatsApp, while still giving you an experience without third-party ads and spam.
Well, the aim is laudable - instead of serving ads to end users, pester companies instead, with the idea that they'll pay to get their communications to you via WhatsApp instead of via SMS or costly phone calls. This could turn out to be a win-win after all.
Anyone know if the requirement to tie the service to a specific SIM card/number has been relaxed, I'm only prepared to use WhatsApp fully if it can be fully account/IP-based, like Skype and most other chat services?