I agree that things have become over complicated (especially when viewing on a small format device) but do appreciate that some change was necessary and I welcome the separate hifi chat and off topic threads as these are quite distinct from Meridian (including Sooloos chit chat).
How about merging Meridian and Sooloos? Often things highly overlap and I do enjoy reading some of the Sooloos items even though I don't have any. We don't have separate threads for DSP speakers or 800 series etc etc so I don't really see any reason why (other than it being originally a separate company) Sooloos is anything different. It may also do Meridian some favours by opening up other Meridian products to other Sooloos users who have stumbled on the site via a search.
Instead of having Meridian, Sooloos and Restaurant in the header, how about moving them up a level so it simply becomes
Forums,
Discussion and
Restaurant which allow unread posts to be seen at a glance which is an issue that others and myself miss - BTW - active topics does not give this information as all options bring up read posts. For us clumsy fingered small touch screen users, if discussion [as it is likely to be the most used option] could be first in the list it would mean that I would not have to aim at one of two lines

Or maybe instead of Forums, simply have home which takes us to a list of forums and the wiki page, making the Wiki more prominent.