One main issue stems from the use of the USB driver for the device, there is no documentation as to the protocols used; several very well versed developers (read: kernel module maintainers) have been trying to get RIM to provide documentation; to my knowledge, nothing has been given over. Most assuredly there are some other things in the way (the more high level items on the command/response structure, for instance) that are also not released to the public; these border on intellectual property rights I bet.
Several groups and/or individuals have been working on reverse engineering the protocols used and have many things working (see the Barry suite of tools), but the process of upgrading an OS is quite a ways beyond a simple chatter to and from the device. It may happen in the future (where there's a will, there's a way) but as a non-programming nerd you're going to get nowhere by thinking just using Wine will do the job. It's far, far more complicated and out of the reach of mere mortals at this stage.