Which futur for the chromebook ?

Hi guys, i'm a young French and I dont' found a answer for my question on the french forum, so I come to you, and forgive me for my eventually bad English •.•

So my question is : Will the old Chromebooks enjoy features recently announces at the Google I/O 2014 ?

And which chromebook do you recommend to me ? The Samsung and the HP (11" and 14"), and the Acer 720P are what I like. And a last question, will my chromebook work after 3-4 years ?

I hope you can give me a better answer than French people :-)

Have a good day ;)