@irrimn - The auction house is an auction house, not a shop. ;) I get what you're saying about your personal style, but I'm with Ankokou in the concern that people who bid accidentally on something with a month or a similarly long time would end up sitting without their money for all that time.
What is convenient for a few people's storage needs is not always the best for the economy, and honestly, re-evaluating price after a week or two seems more sensible than waiting 30 days to do it. And I'm not a teenager, like a lot of gamers are.. I'm closer to the age of a lot of players' parents ;) So I do understand the workings of an economy quite well, because I am old and decrepit.
@Ankokou - Agreed, it'd be less annoying if the items still took up space. I think it is being used currently as a way to circumvent the inventory system, though more often I see that with the items priced at 998989879898 silver.
I also agree that it'd be handy if people could withdraw bids in the event that they bid on something with a long lead time or just found a better deal.
I still just honestly feel it's too long. Even two weeks would move things along better and get people to actually price things in a way so they'll sell and you're not relisting constantly. I've never listed anything for longer than 2 days, and I think I've only had to relist once. ;)
Edited to add: I do think this issue and several others might just take care of themselves by making it so items up for sale still take up space in inventory. But I'm still of the opinion that a month long auction time could be cut in half to encourage people to compete and make a more interesting economy.