Hi all,
Just wanted to chime in on this topic..
I use OMV at home and I think it's a great solution for home users - at present. I would like to point out, that when I download the 32-bit ISO it is because my home setup uses an Atom sat in an ITX and not because I am unsure if the amd64 ISO is what I need. Maybe to solve this problem, the ISOs could be renamed simply with "32-bit" and "64-bit" suffixes to see if the download behaviors change? I realise that OMV can be installed on a Debian system - but some don't. If the 32-bit ISO is to be removed for the next release, there should be clear instructions for the users who are not sure what to do. This way, it will keep faithful followers from wondering elsewhere believing that this project dropped support for them. OMV is presently a home solution, so we can't forget how home users think 
OMV has a hell of a lot going for it. It's Debain based for starters which means... filesystem choice, package choice, HARDWARE SUPPORT! - and who doesn't love Debian?
I like the fact that OMV can be installed on top of an existing Debian installation with no effort. Try asking the two FreeBSD alternatives how to install their solutions on an existing FreeBSD install and you will get the answer "Why would you want to do that? Get real!". Well, like others here, I like GUIs
Another plus point for OMV being Debain is ARM support... Whilst the Pi might not be quite what some are after in a NAS, there are a couple of others like the Cubietruck and the ODROID-XU which show massive potential for low cost NAS boxes. Both have gigabit Ethernet with the Cubie having a SATA port and the ODROID having USB3. FreeBSD for ARM is doesn't support Ethernet on either the last time I checked.
That said... I also agree with those who have said that ZFS should be a core component of the project and that the 64-bit ISO is the way forward - purely to benefit the business environments. At home my focus is on low power so my NAS is an Atom (soon to be ARM) with no RAID - my media center files are synced with an offline backup every week whilst critical data (family photos and videos) is sent to the cloud instantly - thus rendering ZFS useless when it comes to my home setup but it would be great to have OMV recognised as a feasible solution in small to medium business environments and I do think as others have said that this is the key item that would raise OMV in terms of it's competitors - this in turn will attract devs.
Just my opinions on the subject 