i couldn't find Vegemite at the import store i visited in Chandler, but I did find some Marmite, which was also on my to-try list because it is either A) No-name brand Vegemite B)really similar anyhow. I hadn't had Vegemite since I was a kid so it was like trying it for the first time all over again. IT was strange. Im not going to say I like it, and I'm not going to say I hate it. It kept switching flavors on me. It would either taste like delicious beef or a lager beer. I have to say though I had just ate octopus chip puffs before hand so that might have had an influence on the taste.

from reading the article on Wikipedia it would seem as Vegemite is a much milder version, i suppose if i rubbed my toast with butter and then a tad of Marmite it would probably taste like Vegemite.
round 2!
butter improved the flavor of the marmite making it savory, but every few bites i would get an extreme bitter flavor. This is a cause where i need Australian eating advice from an expert Australian.