If I can chip in with a bird owner's point of view...
I hope it's not too presumptuously anthropomorphic to say that the magpie I share a house with has distinct facial expressions (you have to know a bird very well to read expressions without the usual facial features though), language and emotions.
Expressions can be read from position of feathering, raised or lowered eyebrow feathers, angle of head, shape of eye etc.
Language: Pie uses magpie noises, but also human noises he's appropriated (*kiss* and *sniff* noises in particular) which he uses in definable, repeatable situations. The *kiss* is only used in one to one chat when Pie is relaxed. The *sniff* is used as disapproval: "I don't wanna!", "But I wanna!" or if you're eating something not deemed good enough to steal.
Emotions: If you've ever engaged in play with a magpie, you'll know that the curved back, tail in the air, fuzzed-up head, waving wings and mad squeaking denote pleased-with-himself happiness. Magpies are also capable of feeling guilt. They know damn well that "NO!" means "please stop pecking the wallpaper immediately" but choose not to obey, casting backward glances before daring to peck it anyway. There's a totally different set of squeaks and wing-waves that denote "caught red-handed"! Pie is also capable of some spectacular bad moods, meaning that any attempt to touch him or to ask him to step up will be met with huffing, honking and a warning beak in your direction. If you can read the signs of a flapping beak and "wiiich"ing noises, you'll know not to try.
These emotions and behaviours do have an evolutionary advantage. Intelligent scavenging flock birds need to have a good team-oriented working relationship with each other as well as good interpersonal bonds to keep the flock together. But it's also to your advantage when times are hard if you can keep your own cache safe, realise when someone else is watching, and even pretend to hide something (as observed in jays, for example) but in reality put it somewhere else. That demands a lot of intelligence and the ability to not exactly empathise, but to put yourself in someone else's shoes and view a situation from their point of view.
Other birds of mine, the starling and the sparrow for example, I would class as being less intelligent. They interact on a different level and in a less complex way, but still show individual personality traits. While the starling has a vast repertoire of human speech he can mimic, there is a less definable correlation between situation and sound (although that could be because 95% of the time a starling's sound can be categorised simply as "too bloody loud!"). The sparrow's repertoire is more limited, comprising the usual cheeps, but also some more complex song, and an angry ear-splitting chatter reserved for "put me down immediately", "No, I will not come down from the curtain rail", and "Take off that green fleece!" Not sure what evolutionary advantage an aversion to green fleeces has, but the ability to let someone know in uncertain terms that you're pretty damn angry is useful.
I know this is all very much subjective and nothing scientific that would stand up to scrutiny if you tried to make a study out of it, but I do find it strange that humankind finds it so hard to accept that any other creature with a brain could not feel emotion or have intelligence. I've often wondered if the lack of spoken language and (in many cases) familiar facial features means that we have difficulty relating to animals and therefore underestimate their ability to communicate and consciously get the best from their environment.
I'll stop rambling at this point and let you all get back to arguing about semantics
