A horizontal tab bar please!
 

In the past 4 years I have seen many OmniOutliner and OmniGraffle updates and 2 NEW OmniGroup applications (check that, 3 NEW applications: OmniPlan, OmniFocus and OmniDazzle).

Can someone please explain to me what is so difficult about giving us (the Paying Few) the option of having my tab bars be vertical OR horizontal?

Seconded. The tab drawer takes up a lot of screen real estate - a bar would be more functional.

Despite how often this is requested, I wouldn't cross my fingers on its implementation until OW 6.0 at the earliest. Still, it would be nice to have some kind of word from OG.

Yep. An oddly popular request, IMHO (see sig.) I find the graphical tabs much more "functional"

But with the number of requests for it, seems like the prioirity might be a bit higher. Still, the pattern with the 5.x releases has been to make the 5.x feature set more compatible... not so much add features. Some of the features that have been added, I'm guessing are more the result of solving other problems so the "feature" was more or less a side effect or work that had to be rewritten anyway.