Recently the Wp8 version of Whatsapp was pulled from the WP marketplace, leaving users a bit distraught; as Whatsapp has become a standard for messaging in most countries without unlimited texting plans. Therefore one of the folks at welovewp.hk emailed the developers team asking for an update, with which the replied that:
The new update should be 6x faster than the previous version. The new emojii ser will be available in an upcoming update, I’m sorry that we don’t have it yet.
Hopefully the newer version of whatsapp will live up to this 6x faster, since unfortunately the WP7 version still has a couple bugs, mainly the slow launch times. Also mentioned was the background Audio API which allows Whatsapp to stay connected to the WiFi when the screen is locked, although it is annoying it does serve a purpose to those without push notifications; and will stay included until Microsoft fixes this themselves.