Difference between tux and dinner jacket?
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Some 8 years after the fact...
My understanding, from the British tradition, is that a Tuxedo generally has a single button whereas a dinner jacket has two (or even three) and the cut is slightly different. A Tux is more rounded and looser, and a dinner jacket is more geometric and 'tailored.' Hence people being a bit sniffy about Tuxedos - they are far too relaxed!
In the UK the dress trousers are implied in 'dinner jacket' but 'black tie' is a common term (to distinguish from white tie, where full evening dress is worn).
A white jacket is... erm... questionable.
Details - a cummerbund should be worn (black is conservative, burgundy a bit festive); shoes should be properly polished; white shirt, preferably formal; ideally black shirt studs and a white pocket square; black socks (although I really shouldn't have to say this); a folded collar is actually more traditional as winged collars are reserved for white tie; obviously a black bow tie, preferably self-tied, but it can match the cummerbund for a little gaiety. Outerwear should be a black overcoat and white silk scarf but no hat.
These are, of course, rules from the early 20th century, but I believe they hold true. The golden rule is "What would Cary Grant wear?"