I've been looking around in the forums (mainly for OmniFocus and related products) and it seems that this is where people sometimes post and discuss feature requests. The impression I get though is that feature requests are different than comments, notes and distress calls as they can't be given much more feedback than "Yes, we'll look into that". In a forum like this, it is also very difficult to find the feature requests among everything else, and even though they are of a different breed (I think) compared to most things posted, they are hidden by other not very related things. It's also very difficult to know how many people would actually need the specific feature, which makes this a process which can very much be improved.
What about starting a UserVoice app for feature requests (https://uservoice.com/)?
Vote for other peoples suggestions, and OmniGroup would get an idea of what is an important new feature for the users. Also makes it a bit easier to find other peoples suggestions, as they are not hiding as much.
What do you think? I would have loved to post this feature suggestion in a UserVoice forum ;-) but I guess this will have to do :-).