Brand awareness and many normal people will be happy with the features of the current model or are at a stage where they want a new device. You can always use the chance to upsell to the forthcoming model as well. Personally, I'd always wait a few months after a model is released before ordering it anyway (gets the early production problems sorted out, supply/choice is better, in-depth user reviews are available, you can see what problems are cropping up in real-world use, is it better than its predecessor and what value does that give to you, some people start selling at a discount,...).