Has the inflorescence fallen over? Since you are in Australia, you might have different Aloe easily available to you than we do in the U.S.
About how large is the rosette on your plant?
Has it made a trunk?
Do the leaves have any spots at all? If so, top or bottom, or both?
Does it sucker/have pups?
Do you have any other pix (close-up) of the leaves & blooms?
The leaves look much larger & thicker than any A. arborescens I've seen, so I'd also say not that one.

Thank you for your follow up questions Rosemarie;
The inflorescence always falls over, because it is on a long thin stalk. The rosette is about 1 meter across, and it makes a trunk up to 1 meter so far; no spots at all on the leaves, and it suckers and makes pups easily. It makes little pups on the flowers too.The flowers on this pic are from the long stalk of another plant.

Thanks for the additional pic, bnrmember. =) I've been looking, looking (my books/ online), but not coming up with any match. The branched, loose racemes of blooms are not clicking with anything I've seen. Leaves do look so much like A. arborescens. Does it seem your plant will be a single trunk or any evidence of it branching? Any chance of 2 neighboring species producing this as offspring? LOL

The trunks branch like arborescens does, and it grows pups, and also pups from the flowers. It does look bigger than any arborescens I have seen. I got the first one from a campus where I studied horticulture about 10 years ago and the flowers have always been the same. It may have been a hybrid from the start; there aren't any native Aloes in Oz. Mine grows in the shade, would that make them bigger? Thanks for your help Rosemarie.

If it were a hybrid from the start, that would explain things. :P Ha ha! Not saying I can eliminate all others as suspects. From my personal experience, the Aloes I've had growing in shade vary dramatically from ones in the sun. The leaves have been longer & skinnier than their sun brothers.

Another site, with folks very knowledgeable on Aloes, may be able to give you better answers than I. Check out xericworld dot com in the Aloeaceae forum. A lot of experts frequent that forum.

Sorry I couldn't be of further assistance! :(

Something about those flowers remind me of Aloe divaricata or some similar Madagascar aloe.

I believe BP is onto something!! Yay! Aloe divaricata seems like a good candidate on all counts. =) Are the leaves on your plant spaced out on the stem at all?

Rosemary, theres an Aloe forum?

What, Larry? On another site, yes, (name given above, put it together) with many different succulent families represented. Some in depth discussions by many in the biz.

~Rosemarie

You guys are awesome! I think it is definitely a Madagascar plant. The flowers are very similar to diverticata, but there is nothing red in the plant and the sap is clear; also there isn't spacing between the leaves. I had another look at bulbillifera, because it fits with the flowers, bulbils and the look of the leaves, but mine forms stems of up to 50cm sofar. I had a close look a the stems and realised they were solitary, not branching, although they grow in clumps. I saw they can hybridise with others for example with arborescens, so why not with diverticata?
Thanks to Rosemarie and Beachplants,
Mani