R 3.4.3 has been released, as announced by the R Core team today. As of this writing, only the source distribution (for those that build R themselves) is available, but binaries for Windows, Mac and Linux should appear on your local CRAN mirror within the next day or so.
This is primarily a bug-fix release. It fixes an issue with incorrect time zones on MacOS High Sierra, and some issues with handling Unicode characters. (Incidentally, representing international and special characters is something that R takes great care in handling properly. It's not an easy task: a 2003 essay by Joel Spolsky describes the minefield that is character representation, and not much has changed since then.) You can check out the complete list of changes here. Whatever your platform, R 3.4.3 should be backwards-compatible will other R versions in the R 3.4.x series, and so your scripts and packages should continue to function as they did before.
The codename for this release is “Kite-Eating Tree”, and as with all R codenames this is a references to a classic Peanuts episode. If you're interested in the source of other R release names, Lucy D'Agostino McGowan provides the Peanuts references for R release names back to R 2.14.0.
r-devel mailing list: R 3.4.3 is released