I haven't regularly bookmarked sites in a decade or more. The bookmarks are in my head, and I can live with the Omnibar mostly reliably surfacing the things I didn't finish, and later recall and want to pick up.

That said, I'm pretty sure the Omnibar is buggy at finding tabs. I inevitably have several tabs to gmail "open". It ought to be a lot easier than it is to find /return to the last-used gmail tab, and not one of the several from previous browsing sessions. :)