Happy Buddha Restaurant is no longer all-vegan, which is quite a disappointment.
I think they were busy the first few weeks they went "vegetarian included" (as in India there are both "pure vegan" and "veg/nonveg" restaurants), but I'm not sure their business decision was sustained.
I think their main problem in keeping business is that they lodged themselves in the same building as Buddha's Delight, a longstanding all-vegan restaurants, offering a neater and more English-speaker-friendly ambience. But the folks upstairs - Buddha's Delight - are truly friendly, too, though their English isn't "broadcast quality".
We used to take the Vegetarian Meetups (http://Vegetarian.Meetup.com/27) there each month; we moved up to Buddha's Delight after Happy Buddha Restaurant's decision to go "Veg/Nonveg" on us, and the 2nd floor is quieter.
No doubt, however, that Happy Buddha is far cleaner and better looking, while the more spacious Buddha's Delight upstairs is far quieter and always seems to have an evidently vegetarian (likely vegan) crowd.