If you are using latex: latex accepts also png. Not sure, if pdf accepts
"landscape", but this is another point ... many papers accept or require
tiff.
They say. But in my experience, I've never failed to have them accept PDF or PNG even when they ask me to provide TIFF. I suspect that all modern publishers have technology to convert PDF and PNG into the formats they internally use. You have to worry about TIFF only when you produce TIFF images and need an exact reproduction of them. (I mean, the conversion may lead to slight changes in color or resolution.)
As to LaTeX . . . I have the impression that most people use pdflatex, which natively handles PDF, PNG, and JPEG images. You have to convert EPS into PDF or something else to use it with pdflatex. (Also, it seems that there is a command called \includepdf to be used with the regular LaTeX.)
Cheers,
Ryo