OK Melodrama aside, you may or you may not need to rewrite all your meta descriptions. Here’s why.
If you have searched for anything recently you may have noticed a lot more text under each result. Google has changed their rules for meta descriptions that show up in search results. Although meta descriptions are not part of the ranking algorithm, they do play a role in whether people click or not. The change means that Google may show up to 320 characters instead of the previous 160 characters.
This is what Google is saying about the change.
The fact that our snippets have gotten longer doesn’t change the fundamentals of writing a description tag. They should generally inform and interest users with a short, relevant summary of what a particular page is about
What this means is that we now have the freedom to write longer descriptions, however if you are happy with your current descriptions you don’t need to change them. If you’re not happy with them or you think you could do a better job with more characters, now is your change to write a bit more.
What it doesn’t mean is that we should stuff a bunch of keywords and junk in there in order to try to trick the search engines.
As always, Google may or may not use the meta descriptions you write. Well written enticing descriptions that describe the content of the page will continue to be best practice, and will give a better chance that Google will use them and that people will click. .
If you’re interested in reading more about this, check out this article from Search Engine Land.