they talked about it a bit last year
Not sure where your rumors came from but they came out about adding this functionality last year, I don't know how broadly they talked about it but they mentioned they were going to add de-dupe and compression at a small "HP Storage tech day" which had a bunch of bloggers(inc myself) last August.
(from my blog)
http://www.techopsguys.com/2013/07/30/hp-storage-tech-day-3par/
"They didn't talk about it, other than mention it on a slide, but this is the first time I've seen HP 3PAR publicly mention the terms. Specifically they mention in-line de-dupe for file and block, as well as compression support. Again, no details."
And in case your rumor mill is sounding any other things, another feature they announced at this event last year was adding native file+object controller functionality to the 3PAR as well (mentioned in above blog - no details other than they were planning on it of course plans could change between then and now)
If you want to see the source HP posted videos of the event here
http://h30507.www3.hp.com/t5/Around-the-Storage-Block-Blog/Videos-from-HP-Storage-Tech-Day-4/ba-p/143191#.U4i3C_EpKIA