After the winter update fiasco (R8 overpowered weapon), Valve has released a new and huge update. Even though the highlight of the 1.6 GB update is the new Operation Wildfire, there are some tweaks to a couple of maps, too. According to various sources the update is surprisingly well received so far.

For the full list of changes check the release notes.

EDIT: Valve released a new update 122 MB in size. Now dealing mostly with bug fixes.

Also note that ESL Pro League and ESEA have rescheduled some of their upcoming matches due to the update.

Links: Counter-Strike Release notes, Counter-Strike Operation Wildfire, Twitter ESL tweet, ESL ESL Pro League