I didn't find much on the list that surprising, but I do think that there are some big hints at more theme turnover in the future, smaller production runs, and a shift to a 2 year shelf life instead of the 3-5 we have been used to. Its a rough business model for collectors as they have to buy everything more quickly but if kids are your primary target there is (for some reason) a "need" to change sets all the time.
-I think the cavemen were designed as a learning tool/classroom diorama type line so once everyone bought them for that they ditched the line as additional sales were unlikely (much like the Egyptian line IMO)
-Soccer stuff will be out again next time they think it will sell... so it is just shelved... I dare say same with the Olympic stuff
-Dragon Knights are being replaced by Fairies... so that makes sense
-That house has been around for a while
-Legitimately sad to see the Ferry go... but how many people are really going to buy a bunch of those? I did not see the Harbor itself on there though so perhaps looking good for the return of the Suzanne?
-A few sets here and there from various themes are probably just being replaced by newer versions/sets... Top Agents is getting a few new sets so it makes sense to take a few out.
-Future Planet just costs too much I think... all the "extras" that they put into it make it a hard sell... perhaps they will be retooling and taking out some of the Tech to make it a more affordable TOY instead... and not having good guys and bad guys but cooperative space exploration (that we can make our own good guys and bad guys with) or focusing more on near future space instead of far future... and they probably also think they need to release pink aliens
I AM SHOCKED! That the 123 Castle is being discontinued... it is a lovely set... though perhaps they are just retooling it so it is expandable?