Bug#420078: Correction (root image missing, boot image is fine)
The image which is missing is root.img, not boot.img.
Looking at build_floppy_root.log (http://people.debian.org/~joeyh/d-i/images/daily/build_floppy_root.log)
It does seem as if the required files cannot fit on a single floppydisk anymore.
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