The NHD Update tool v6.0.0 for ArcGIS 10.1 is in the final testing phase and will be officially released in February. Subsequent versions of the ArcGIS 10.1 tool (v.6.0+) will include enhancements submitted by the stewardship community. Release date for the first v6.0+ will be one-two months out from the February v6.0.0 release. Note that only the most recent version of the NHD edit tool will be maintained/enhanced. Issues reported regarding earlier versions, will be tested in the latest Beta version and resolved as necessary.
Please check back to the Hydro Resource Center for the final release!

I have downloaded the ArcGIS 10.1 NHD Tools, but I cannot get it to install. Are there any known issues with the installation of NHD Tools on ArcGIS 10.1?