No, there is a Swiss High German in my opinion. They might be extremely similar, but the Swiss are sometimes prone to use words that are not used in Germany, and occasionally change genders. This is not done intentionally. I would consider it to be a difference much more on par with American and British English. Nevertheless, the difference exists.

I might as well make a late edit instead of flooding the post. I know what the difference between "High German" and "Swiss German" is. I am just saying that the Swiss carry some of this over into their version of High German, whether or not this is grammatically correct. In addition, they use a lot of foreign words (French and English, for instance) which are not used in proper High German, but function perfectly well here. Oh: and the ß was also abolished here.