True. (and the songs aren't even that much alike IMO) Of course he has the same distinctive sound and the same songwriting process. Of course it sounds like "him". People's own creations just shouldn't be taken away from them.
There's an assumption here that the assignment of the copyrighted works was lawful. I don't have all the facts here, so I can't give you a clear opinion. However, I've been able to attack a few agreements like this by voiding the initial transfer. You may have an out under your state's property or contract law. As always, I suggest consulting an attorney to look over your assignment documents, and to discuss any potential circumstances that may void the assignment. Good luck.
Yeah, that was an important ruling because it essentially said that you cannot copyright a "style" particularly if that style is inherent to who you are as an artist. This is EXCELLENT advice.
Copyrights have not been 28 years for a long time. The current length for copyrights is life of the creator plus 70 years. You can blame Mickey Mouse. Disney lobbies hard to make sure they retain copyrights over Mickey Mouse.