Konami has re-released a number of titles on PC recently through GOG, including Castlevania, Contra, and most recently, Metal Gear, Metal Gear Solid, and Metal Gear Solid 2.
It seems Silent Hill 4 will be the next game to see a re-release on the DRM free store, as a new rating has appeared for the game on the PEGI website, where it has been rated 18 for "graphic violence." While it's not confirmed, this same re-rating was seen for other Konami games shortly before their release on GOG.
Silent Hill 4 was released way back in 2004 and features a combination of first-person and third-person gameplay. It's also the final game in the series developed by Team Silent, and while not considered the pinnacle of the series by many, is still a very solid entry.
Much like the other re-releases on GOG then, we're expecting this will be the original PC port from 2004 re-released on GOG DRM free, with the bare minimum of fixes to allow it to work on Windows 10. I wouldn't expect any more than that though - some were left disappointed at the relatively unchanged nature of the Metal Gear Solid releases, which lacked any additional features or fixes from their early 2000's releases, such as widescreen support.