I remember reading that they were going to post the conversion from SR3 to SR4 on the shadowrun website, but I can't find it anywhere. Does anybody know where I can find it? I am going to convert some old characters next weekend and would like to see the official rulings.

Rebuild the characters, spend karma, equip them as they should be, without worrying about money - thats about the only conversion possible.

I think they were planning on doing that before it became blatantly obvious that it wasn't possible. It's like converting SR3 characters to D&D. Does not work.

Hyzmarca's shot at it, roughly equivalent to my suggestions below. You might find his Attribute math easier:
http://forums.dumpshock.com/index.php?showtopic=9698

Here is my version of the quick conversion. I haven't seen much to motivate redoing it:
http://forums.dumpshock.com/index.php?show...451#entry294704

Both these suggest liberal eyeballing, but it should get you close enough to start with to do that.