Meat lovers do sometimes complain about the taste of veggie burgers, but I find that people -- at least around Madison - are happy to eat a veggie burger without feeling a need to declare themselves vegetarians.
There are many variations on the veggie burger, so many that they should really have different names; lumping them all together under one heading isn't really helpful, or fair. Maybe it would be better if we stopped calling them burgers and just thought of them as sandwiches.
Bharti Kirchner, author of Vegetarian Burgers, divides them into "Grain and bean burgers," "Vegetable burgers," "Nut and seed burgers" and "Tofu and other soy burgers." Trying all the recipes in this little book could keep you busy for a long time.
New York Times food guru "Hearty Winter Vegetable Burger" (with beets), a "Fresh Spring Vegetable Burger" (with asparagus and peas!), a "Midsummer Vegetable Burger" (corn and zucchini), and a "Spicy Autumn Vegetable Burger" (kale or mustard greens and a sweet potato). He also includes a good one for a "Fast Nut Burger." Some of these more delicate-flavored patties can get overshadowed if you use a really good, standup, whole-wheat bun. A bun that's a little more shy and retiring works better. (This article covers much of the same material as the cookbook.)
The "Smoky Chickpea Burger" was one I had high hopes for, but it didn't have that much taste; I blame the chickpeas, which may be too mild.
I also had high hopes for this recipe for "Wheat Berry Vegetable Patties" (which really does call for a "splash of umeboshi vinegar"), but mine fell apart. It would work, I think, as a good veggie crumble in a chili recipe.
This vegan red bean-chipotle patty has the right idea -- kidney beans for a bigger flavor, combined with tomato paste and canned chipotles -- but the brown rice and the oatmeal, too much. I'd pick one, maybe the rice.
I cannot claim to have tried this one, but maybe next fall, when the apples are fresh: The Apple Burger. Actually, if you're not trying to mimic the taste of hamburger, you can make a patty out of almost anything. Experimentation is fun. Use peanut butter and banana for an Elvis burger, or peaches and avocados in a Ginsberger, perhaps?