Embedding charts into a document is one of those basic office app functions that you take for granted. It's important that you can do it, but you may not see an obvious way embedding charts could be improved. Google did, though: rather than re-embedding every time the underlying data changes—which would require deleting the old embed and adding the replacement—you can now just click a button to refresh the chart.
This is one of those details that won't affect the workflow of a lot of people, but for those it does affect it will be a huge timesaver. If your organization shares a lot of documents, for instance, you might wonder if the graphics have gone out of date.
With this new feature enabled, it could be as easy as hitting a button to see if the original spreadsheet has undergone any changes. And this is without requiring full access to the underlying spreadsheet. More important, it means you can do that on any number of documents instead of needing to go through a longer, manual process for every presentation or write-up that used the outdated chart.
Here's a great GIF showing things off in action:
Importantly, this is not an automatic update. For some, you might see this as a negative since you're still stuck with things to remember and people without edit access on the document/slides can't force a refresh. On the other hand, this keeps people from accidentally botching production-level items just because they were fiddling with a seemingly unrelated spreadsheet.
And if you're determined to use an older version of the chart for whatever reason, you can simply unlink it any time to preserve it in the state you had it in the document you're working in.
For now, this is a feature for web users. The charts will be visible on Android as usual, but you can't use the linking/refreshing features without opening up a browser.
- Google Apps Blog