What's App has updated to Version 2.10.1 for iOS and moved on to a model which it was using in other platforms. The first year free service and subsequent 1$/ year rental. The existing buyers need not have to pay for it eventually.
Version 2.10.1 features
iCloud chat history backup and restore: WhatsApp > Settings > Chat Settings > Chat Backup - back up both chat history and associated multimedia into iCloud
Multi-send UI: can send multiple photos at the same time - a useful option which helps people save time
URL schema support for 3rd party apps : The applications need to be updated for this by the respective developers