Layoff notice, what does the 60 days mean? - any advice?

I received a formal notice about a mass layoff at my workplace. It has been a long 5 weeks. Some colleagues are already leaving. Should I stay for the bonus?

Write down key dates and keep copies of the notice. Mine helped when a question came up later.

Thanks for writing this out. I went through something close to it 3 months ago, and it got easier once I kept a simple log of every call and form.