Are you on Facebook? If not, none of this will make sense.
Anyway, it really irks me when someone sends me a friend request and then never says anything to me. I mean, it's not necessary to write 5000 words to tell me how you're doing or ask about my life or whatever, but a little something to say I'm not just a notch on your friend count belt is appreciated.
This is the sort of Facebook app we really need. No more stupid quizzes and games - I want a friend filter app. It only permits your updates to show on my wall if you and I have had a conversation using Facebook. It can be via status message comments, wall postings, private messages, whatever, but it has to occur before I see you in my news feed.
Another option is a badge for your profile that shows what percentage of your friends you've had a conversation with in the last month. Then a filter by percentage - if you're percentage is below, say, 50%, you get blocked from my news feed.
So, if you're a company out there looking to make a Facebook app to help build your brand, don't try to make one that does whatever your website does, only Facebookier. It will suck. Make one that's actually useful, and slap your logo on it.