"Wireless communication is via Bluetooth, which has several advantages. First, there's no latency, and the mouse operates perfectly even if you're several meters away - you'll notice no difference at all compared to a wired mouse. With the dongle provided, communication is established instantaneously."
Are you retarded? YES THERE IS LATENCY. Why do you think Razer spent so much time on creating the Razer Mamba instead of using Bluetooth?
Bluetooth is no-where near a wired mouse and YES YOU WILL NOTICE THE DIFFERENCE.
There is latency with this Bluetooth Mouse. I didn't notice it so much with the Microsoft Wireless 5000 bluetooth mouse, but occasionally notice it with the MS Presenter 8000 mouse, but only rarely, and that is when i have a lot of tabs open (45+ tabs) or CPU intensive. The advantages of the presenter mouse however out-way this minor disadvantage, but that's personal opinion. This is a great mouse, and lag/latency is almost non-existent, i've noticed various users of this mouse don't experience any latency anyway.