Sebastián Piñera got hammered in the latest CERC poll (their site seems to be under construction so I can't find the original report). His approval is down to an Alan García-ish 35 percent, with 53 percent disapproval. That is consistent with the 36 percent that Adimark reported in June. Mirroring the Concertación years, however, this does not mean a boon for the opposition, which is also viewed with distaste.
So despite all the vaunted Chilean political and economic successes, Chileans are not all that happy with their elected leaders. If you want to understand the big picture of why, then read my co-edited book on the Bachelet government. As for the more immediate causes, read Robert Funk's post on the topic (you can also read his chapter in that book):
So with thousands participating in street demonstrations in favour of better public education, the president responded tonight with a televised announcement: The plan includes a new education fund, improving access and accreditation of universities (he didn't say how), creating a new bureaucracy for universities (he didn't say what) which would, amongst other things, seek greater transparency in order to determine which universities are for-profit, something which is currently illegal in Chile.