I was walking through Borders at Chatswood when I noticed the promotion for $20 credit upon membership application.
You need to activate your card (ala Rebel sports) online.
As the promotion has just commenced today, the salesguy said that there may be some teething problems.
Mod: Changed to direct link
mod Also note, some members write that you have to choose to pick up the card in store or the card will not have the credit on it.
One member wrote that the credit lasts 1 month only.
Update: No email from Borders as yet to confirm my membership application although the Saleslady suggests their IT department is working on the problem - should be rectified tomorrow Sat 13th although I wouldn't hold my breathe.
I saw this mentioned on Whirlpool today too details mentioned were as you have posted