|One of the Sunday colour pages, featuring the Kzinti|
Assuming that is the case, the format of the original comics will provide interesting editorial choices for IDW. There were originally daily black and white, strips, plus a colour version on Sundays. Owing to the mixed audience of daily and weekend newspaper readers there was overlap in the two different formats. It will be interesting to see if IDW attempt to rationalise the stories, and maybe if they recolour the whole thing, as they have done with some previous release.
Hopefully a similar release of the TV era UK comic strips (some of which featured some rather impressive artwork) will follow.
You can find out much more about the US strips on Mark Martinez's Star Trek Comics Checklist, and Memory Alpha.
Update: IDW editor Chris Ryall has confirmed these are what they seem, and will be released as one of IDW's Library of American Comics books. He also noted they'll have a better title! - I guess that means little hope for those UK strips, but it should been a very high quality archival treatment of these American ones.