The new model is said to have better battery life - around two hours extra - though it might not be just the battery itself that's had an upgrade.
It could also have a new processor, too - we know from a recent listing with the US regulator that Nintendo was planning to change the SoC (System on Chip), type of storage and CPU board in the Switch.
Of course, an improved processor and mainboard could also contribute to the improved battery life through increased frugality.
Coincidentally, we're still expecting a full Nintendo Switch 2 refresh at some point, although the fact Nintendo has upgraded the current model is probably a sign that we won't get it until 2020 at the earliest.
Nintendo US has also just announced some new Joy-Con colours, although we're sure they'll come elsewhere - One set is blue and neon yellow, while the second is purple and neon orange. They'll be available later in October.