They were supposed to have these apps a couple years ago. Many people dropped BB when their BBM buddy list emptied out. The best way for Blackberry to retain those customers is by having BBM on other devices. It would have been more beneficial 2 years ago, but it should still help BB nowadays. IIRC, BBM on the other devices will be limited, allowing communication from BB users, while trying entice iOS and android users to BB to enjoy the full features of BBM.
According to the article it sounds like it will be full fledged version:
In the first version of multi-platform BBM, iOS and Android users are expected to be able to experience the following BBM features:
The immediacy of BBM chats
Multi-person chats
Voice note sharing
BlackBerry Groups, where BBM users are able to set up groups of up to 30 people and share calendar, photos, files and more
The stats are pretty immpressive I think as well:
BBM Quick Facts:More than 60 million monthly active users
More than 51 million daily active users who are connecting with friends or colleagues an average of one and a half hours every day.
BBM users send and receive more than 10 billion messages each day, nearly twice as many messages per user per day as compared to other mobile messaging apps
Almost half of BBM messages are read within 20 seconds of being received; indicating how truly engaged BBM customers are
And this new feature sounds cool as well:
Today, BlackBerry also announced BBM Channels, a new social engagement platform within BBM that will allow customers to connect with the businesses, brands, celebrities and groups they are passionate about. BlackBerry plans to add support for BBM Channels as well as voice and video chatting for iOS and Android later this year, subject to approval by the Apple App Store and Google Play. If approved by Apple and Google, the BBM app will be available as a free download in the AppleŽ App StoreSM and Google Play store. Additional details about system requirements and availability will be announced closer to the launch.