Given that many big name CE firms are not overly profitable (as a result of too wide, shallow product ranges I would argue) I think you're right, they will start to go down the Apple route - given how profitable they are with their current model.
To your question a: do we really need 6 versions of the Xperia?
Yes. Having worked at a CE company for a while, I do know that the name of the game for many CE venodrs -- until Apple came along -- for decades was to roll out as many variations as possible of essnetially the same product to meet different customers' tastes.
No respetable CE vendors just launched one model like Apple did with iPhone. They made insignificant tweaks for every product, gave different product number and sold it.
To me (and the general public) the name is the whole thing that relates to their product ie Xperia M or Xperia L etc. My point is a:do we really need 6 versions of the Xperia (beating in mind that they have other ranges of phone) and b: if you must then atleast give the customer a context or framework that makes those numbers and letters releavant to them.
Something simple like Xperia Lite, Xperia Pro, Xperia Photo, Xperia Media, Xperia Family etc. These are somewhat naff but I know where I fall in that range.
At the risk of being pedantic the HMZ-T1 came out in 2011 so I'm sure Sony could have trademarked "Glass" it if they wanted when they went in to the design phase. Anyway, Sony Immerse would have been pretty good too.
Totally, word of mouth is the cheapest (and best) form of marketing so if people can't remember what it's called - it isn't going to get passed around. Also, it makes things sound really technical and complicated when really people just want "The best TV $800 can buy".
I have had this conversation over and over and over with friends. Some companies simply don't get it. Sony and Samsung are particularly bad about this. Toshiba did this with their laptop lineup, sure they may say satellite, but there are 700 variations under that name.
Word of mouth is a strong force and if people can't recommend your product even when they want to, you're doing it wrong.