Ask yourself these questions before you enter an interview;
1) Do I have a clear idea of what I'm going to ask in today's interview?
2) Have I practiced how I will handle difficult questions such as 'why did you leave this or that job', 'why do you have so much movement on your resume', 'what do you know about our space', 'why do you want to work for our company', and 'what sort of money do you need to make'.
3) Did I think about how I can illustrate to the employer that I can come up to speed quickly? This includes having a bulletized hit-list of correlations that you can make between solutions that you've sold and how you think they apply to the hiring company's offering, as well as which verticals you've sold in to and price point and complexity of solutions.
With everything going so fast in today's world, when you accept the responsibility of taking an interview you must accept that you, too, will accept the responsiblity of taking the added time and measures to sit down and prepare for this interview like you would a sales call. Make yourself shine and while you're at it make your recruiter buddies shine, as well!!!