I received that one as well, and as an AGL customer who didn't read it properly very nearly clicked......but it referred to electricity and I only use them for gas so looked a bit more closely.
Lesson learned, don't rush if you think of clicking.
One good aspect of GMail is that it automatically shows the true email sender's address if you go so far as to look at the email.
The AGL email scam is pretty good - correct number of digits in account number (that makes a change). However, given the number of gas customers they have...
Also, the amount of the bill would probably be ball park for around 30-40% of their customers.
I guess John Patrick may have been fooled into clicking.