My reading of that suggests you won't be able to charge for 'point' upgrades but you would for new versions. I don't have a problem with that - anyone who charges money for a .1 update deserves a kicking IMO. Agreed it seems to mean you won't be able to offer upgrade prices to purchasers of previous versions though, which is a pain. So essentially you'll have to make sure each new version has enough new stuff in it to justify people paying the full price again. I don't really have any objection to that either but it's going to make life interesting for some companies who seem to put out new versions that barely differ from the previous one...
At the end of the day though the Mac App Store isn't compulsory so if you don't like the terms, you just don't use it. Plus they've got what, two years to amend the terms if one of the 400lb gorilla companies objects...
Jon