You lost. Get over it.
Hugs & Kisses,
Okay, that's a teeny, tiny bit oversimplified. Nevertheless, I'm a tad bit baffled at the "debate" about the legality of Kosovo declaring independence, for a number of reasons.
1) This is really always a political question. I mean, we can dither about the legality of unilateral declarations, the Supreme Court can issue a decision on it (Reference re Secession of Quebec,  2 S.C.R. 217), but the fact of the matter is a state is a state if and when other states agree that it is a state, the anomaly of Taiwan notwithstanding. This is a political question, and you can't put the rabbit back in the hat later by saying it broke the rules.
2) As the international Covenant on Civil and Political Rights puts it:
1. All peoples have the right of self-determination. By virtue of that right they freely determine their political status and freely pursue their economic, social and cultural development.
And as the SCC noted in the Reference re Secession (at para. 114):
The existence of the right of a people to self-determination is now so widely recognized in international conventions that the principle has acquired a status beyond "convention" and is considered a general principle of international law.
Self-determination is generally though of in two contexts, both involving the domination of a people by an outside force:
The right of colonial peoples to exercise their right to self-determination by breaking away from the "imperial" power is now undisputed...
The other clear case where a right to external self-determination accrues is where a people is subject to alien subjugation, domination or exploitation outside a colonial context. (Reference re Secession at paras. 133-34)
Clearly Quebec, which gets all sorts of free rides and special treatment from the Canadian government, doesn't fall under those categories. But I'm pretty sure Kosovo does.
Kosovar Albanians are a relatively homogenous national group living on a relatively discrete chunk of Europe who apparently cannot be part of Serbia without the two sides killing each other. Sure, there are examples of multi-ethnic states succeeding, but they have characteristics, like integration, or a supra-national identity, or most importantly, not killing each other. Both theoretically and functionally, Kosovo is a textbook example of why/how self-determination is so important.
3) How is this news to anyone?
Kosovo has been de facto seceded from Serbia since 1999, when the UN declared it a protectorate. Yes, there were attempts to negotiate a mutually acceptable status, but once they fell through, all bets were off. I don't think it says anything that the UN has yet to acknowledge Kosovo; I think they're basically being polite, to avoid the appearance of having instigated the whole thing. If I am surprised by anything, it is that it took this long for a declaration of independence to be made.