I wonder to what extent Google's algorithm takes "subliminal" inbound links into account? I call "subliminal" links that supposedly have no SEO value, i.e.
- links to my site from blogs etc. with nofollow
- non-hyperlinked urls to my site, i.e. example.com (without a href)
- my company's unique name being mentioned on various pages without any link to it
- links to my site contained in the billions of GMail messages being processed each day
- and similar
I know that all the above links are not supposed to help my site, but I can't help wondering if:
- Maybe they do indeed have a positive effect, albeit reduced?
- Above all, maybe it is their absence that has a negative effect? I.e. if my website has 10,000 inbound links, all regular, and none with nofollow, does it not look suspicious and over-optimized (and should I consequently get a few nofollow links as well, to look more natural)? Similarly, if my website has 10,000 inbound links, but its domain never appears in any GMail correspondence, does it not look suspicious too, and can it not generate some kind of penalty?