The firmware updates were detailed on Reddit – as spotted by Win Beta – and are apparently rolling out now.
Once applied (and after a reboot, of course) you’ll hopefully notice a difference in terms of the way the pen performs, and responsiveness of the touchscreen in general.
Some of the commenters on Reddit noted that the touchscreen seemed to be less laggy post-update, and that the performance of the Surface Pen was clearly much slicker in OneNote.
Handy boons indeed, plus the updates also include new drivers for Intel Smart Sound Technology, ironing out some problems with flaky sound on the Surface devices.
You can manually check for these updates by going to Settings – in the Windows Start menu – then click Update & Security, Windows Update, and then select Check for Updates.
Last month’s round of patching for Surface devices improved stability when returning from sleep mode and also made battery optimization tweaks, again some useful improvements.