Here is another keyword writer. I guess there are many others, I wrote this for myself because other apps did not do everything I needed. It is free and uses exiftool .

It is called 'Do Keywords' there is no help\instructions anywhere else (yet) not even made a web page for it, (actually not sure if it worth it, I have posted this on another forum and got zero feedback:)) Anyway, my last attempt to share this.

Screen and brief description:


(I hope this explains everything)

There are no image thumbnails, folder navigation etc. - just use Windows Explorer for that.

Type in caption, title abd keywords and drag & drop file(s) from Explorer on buttons ('to write' \ 'to read'). That's it.

Features list
-can do multiple files on 'to write' i.e. apply to batch
-remove duplicate keywords and sort them (sort is optional, see settings)
-counts keywords and chars in caption as you type
-spell checker (en-US only for now)
-use space as keyword delimiter (paste an article from wiki, get keywords... need to clean 'the' 'with' 'of' though)
-backup source jpegs (by default, back up is done by exiftool)
-option to rebuild exif data (helps if exif is broken)
-add optional e-mail\author\copyright fieds (in settings)
-for editorial caption, can add IS\SS prefixes, drop file on 'to read' to get exif date before using
-can remove all exif data before writing
-copy to clipboard title + caption + keywords as text
-hints: Cntrl + D to clean up keyword, Cntrl+Z/Cntrl+Y for undo/redo plus whatever WPF supports by default

Can download installer from my newbielink:http://viewfactorimages.com [nonactive], look for 'Do Keywords' on right side

(I do not promise support or adding features, unless find them usefull (for myself)))). So use it 'as is' and enjoy or ... just delete )