Predicting our Singularity future is sometimes derided by skeptics. Bizarrely the critics actually appear offended when a date regarding what will be possible is given. Deadlines and forecasts are not inherently implausible therefore IBM, a highly respected organization, made a forecast in 2011 for a low-power supercomputer (one ExaFLOP/s) the size of a sugar-cube sometime around 2021 or earlier.
You can't really give an overly specific date for the Singularity but you can give a deadline of no later than. Humans use deadlines often as guidelines to help model behavior in the present. Making forecasts is valuable, it helps farmers growing crops, it helps engineers, or it helps socio-political policy formulation. Forecasts have a variety of uses. Awareness of the future is vital.
Awareness of past, present, and future are crucial aspects of being human, of being intelligent, it allows us to shape reality in an intelligent way even if it is merely planning for a summer holiday, or planing to repair your home heating system before it breaks down, or having the foresight to put enough gas/petrol in your car for a long journey. Dates in the past, present, and future are vital. Perception of time and our relationship with it is very intelligent. A Singularity deadline is therefore a very good idea. There is nothing wrong with a forecast such as 2045.
The Singularity could occur in the late 30s but I opt for 2045 to counter possible over-optimistic predictions, which have previously been made within futurism. I would rather have a safe deadline of 2045 than wrongly predict a date too early.