I'm using Centos 7.gnome-shell --versionGnome Shell 3.8.4does this mean I'm using Gnome 3.8.4?  can I upgrade to Gnome 3.10?Are there any how-tos?
Gnome 3.8.4 can I upgrade to Gnome 3.10?
centos;gnome3
Q1: does this mean I'm using Gnome 3.8.4?Yes you're using GNOME 3.8.4 from that gnome-shell output. Q2: can I upgrade to Gnome 3.10?Yes but I've found no repositories that offer it as of yet so your only recourse is to compile it yourself from sources. You can make this a little less painful by trying to use the source RPMS (SRPMS) from a Fedora release that offers it, that's close to CentOS 7. F19 + F20 would be good candidates.I'll warn you though that this can be trick to do yourself, so I'd probably not attempt it myself.Q3: Are there any how-tos?None that I was able to find. It's typically the case that you're picking CentOS because you want ultra stability. The cost of this stability is that you lag behind in versions.If you truly want to use GNOME 3.10 then you're much better off moving to one of the Fedora releases, specifically F20 or F21.