I personally only vote 7 of the top 20 witnesses, Most of the people I vote for are either people I've met IRL or have talk to on more than one occasion online and generally know enough about, or are makers of a project that I wish to support.

It's really almost too easy to become a witness these days.. Just purchase a privix vps and load up the hive-in-a-box image and bam you have one running.

Doesn't decentralize the chain much at all since all the node are running with the same company (don't get me wrong privix is a great company just we don't want all our nodes running in one place company wise)

(shameless plug warning)
Like for instance my witness node runs on my home computer where I have full control over every aspect of it. (its a beast of a computer)

^{Communities I run: Gridcoin (GRC)(PeakD) / Gridcoin (GRC) (hive.blog)| Fish Keepers (PeakD) / Fish Keepers (hive.blog)
Check out my gaming stream on VIMM.TV | Vote for me as a witness!}