CORRECTION
Zermatt has extended it's winter season till May 8th (not included). The biggest mountain will remain open including park and pipe. This made my day.
After that only the Furggsattel chair is open. This one serves two red slopes between 3365m and 2939m. They're good slopes, and you could still get powder..
And if you are willing to hike there's still a shitload of terrain available.