Apple have recently sent out a surprise invitation to their HQ in California. As the picture says, its all about the mac (since this year has been mainly based around iOS devises) and we are expecting some exiting things:
1) Mac OS X 10.7 Lion - the next major release is said to be announced tomorrow. People say it will have touch based interfaces and possibly face-time.
2) A new MacBook Air - this has long been overdue for an update now. It will have more USB ports, more RAM larger HDD space and possibly a disk drive (apple has taken these off the shelves in their retail stores now).
3) A possible a new software range, iLife and iWork? - iLife and iWork are also now overdue for an update. We are still awaiting that "just one more thing" moment.
The event will be streaming live (I think) at 10am San Francisco time and 6pm London time.