forums.wsusoffline.net

today's weight of wsusoffline-wxp-plk.ISO --> 1.46 GB (1,574,576,128)
but 11.04.2014's weight ----> 1.48 GB (1,593,886,720)

1.
Is it possible that today's ISO is lighter? Is any known trend...?

2.
http://www.pcworld.com/article/2150248/microsoft-backs-down-will-fix-internet-explorer-vulnerability-even-on-windows-xp.html#tk.nl_today
- does today's iso include it?

1. If superseded updates were bigger than the new ones are, or if more updates have been removed than added, it's entirely possible.
Further possible reasons:
-support for german patches removed through the batch file, actual removal at next download run
-download of Defender signatures failed and thus missing on ISO (happens frequently for me)

Consult the download log for enlightenment.

2. If you do a new download run now, the new MS catalog will be downloaded and used. The latest updates are in there. For some reason IE6 patches aren't included, according to another post.