I installed facebook 1.5 yesterday and then last night played around with it to see what the differences were.
Anyway, i found that you could sync your BB contacts with your face book contacts and it would download their pic to your BB contacts and you would have this nice link between the 2. Great.
So I went ahead and linked about 20 of my friends and collegues. Then I exited out of that screen and saw in my mail list, facebook and blackberry that the application automatically sent a request to EVERY facebook friend that I do not have their phone number and that I would like it. EVEN if my BB contact information had a phone number it STILL requested one. It only checked to see if the facebook contact info had a phone number.
I have not received any replies back, but you might not want to link your contacts if you don't want the BB facebook sending out crazy requests.