There's a scam email doing the rounds right now which invites people to take part in a Westpac competition to share your best saving tips. While Westpac is running such a competition, the email has nothing to do with it: it's just another classic scam mail which links to a dodgy site entirely unconnected to Westpac.
Westpac has a warning about the scam email on its Facebook page. When it comes to banking, the best rule is the simplest one: they're not going to send you any emails, so anything purporting to be from a bank should be ignored, whether it's claiming to be a transaction update or a competition promotion.
Bank scams are common online, but not exclusively found there. If you receive a phone call claiming to be from your bank, be equally cynical, ask for a number to call back on, and verify the number before you do so.