Well that was unexpected. My 8X, which is an unbranded UK variant, has just received 2 updates today. With PfD enabled, an 'HTC Update' arrived. When it finished, I re-checked and it proceeded to pull down the 8.1 Update (8.10.14219.341). That second one was weird since I already had 14219.341 which arrived on PfD back on 05/12/2014.
Previous Firmware/Bootloader 3030.0.41201.401 / 0.0.3030.0(175731)
New Firmware/Bootloader 3030.0.52001.401 / 0.0.3030.0(181178)
As to what has changed, I've only noticed 2 things so far. The store no longer has an 'HTC' or 'O2' category. Secondly, the HTC app live tile works again! The thing is though, without it being triple-wide tile, it just doesn't look right anymore when 'Show more Tiles' is enabled so I've removed it again but nice to know it works.
Previous Firmware/Bootloader 3030.0.41201.401 / 0.0.3030.0(175731)
New Firmware/Bootloader 3030.0.52001.401 / 0.0.3030.0(181178)
As to what has changed, I've only noticed 2 things so far. The store no longer has an 'HTC' or 'O2' category. Secondly, the HTC app live tile works again! The thing is though, without it being triple-wide tile, it just doesn't look right anymore when 'Show more Tiles' is enabled so I've removed it again but nice to know it works.