work out before weigh in?

I am currently on the SW Extra Easy plan and have my weigh in tonight. Unfortunately, I had to skip the gym yesterday so was thinking about doing a quick jog or exercise DVD tonight before my weigh in.
Is this wise?
I've heard conflicting reports:
a) I will put on weight because of the amount of fluids (water) I will be taking on during the exercise.
b) I will lose weight before the weigh in due to the exercise so I won't be weighed at my "true weight".

Can someone please shed some light on this? I'm so confused :sigh: and don't know whether to work out or not!

As far as I'm concerned exercise is a good thing. If you do weigh a bit more or a bit less this week it will sort itself out by next week. Don't not do your exercise just because you want a good number this week. The idea is to be aiming for the long term and if you want regular exercise to be part of your future self then keep it up. I work out before my weigh in sometimes and I haven't noticed a particular difference. So if you want to do some exercise I say go for it!