Roughly 2 days before the official global announcement, Nokia Mobile stated via Twitter that they indeed have a global announcement in 2 days and provided the link to follow the announcement live on Facebook.
Considering that the global Twitter and Facebook profiles got involved, even organizing some kind of competition to be invited to Nokia Mobile announcement in London (if you’re from UK and pay for your trip, but you get a smartphone), the announcement of new devices seems most likely.
The #NokiaMobileLive event starts on 4th October at 17.00 London time, and for details about your timezone the simplest way is to visit this Facebook link of the event. You can also go to Twitter and like this tweet to get notifications from Nokia Mobile about the event. A YouTube link isn’t provided, but I hope it will be because a lot of people don’t use Facebook or Twitter, but would still like to see what Nokia Mobile has to offer.