I tweeted yesterday:
Algo aprendí hoy (para Twitter o SMS): q = que, xq = porque o por qué, y xf = por favor. También, “twittear” y “textear” son hilarantes. :)
Googling a bit produced some folks more concerned with the neologisms not being in the dictionary rather than the fact they are already being used in the wild. And not just with the kids — witness the social buttons on muyinteresante.es:

Coincidentally, muyinteresante.es had this story today, “¿Existe algún diccionario que incluya la palabra ‘tweet’?”, asking if there is some dictionary that includes the word “tweet”. In fact, the OED is adding “tweet” in the contemporary sense:
The noun and verb tweet (in the social-networking sense) has just been added to the OED. This breaks at least one OED rule, namely that a new word needs to be current for ten years before consideration for inclusion. But it seems to be catching on.
We’ll have to see if twittear and textear wind up in the DRAE at some point. Ya veremos.
