This is like one of the question that everybody likes to ask the pro, so I never really got an answer for that myself, until I saw a video of “Matt Cutts”, head of the Google Spam team.
He explains in his video that if you have multiple sites that are particularly about the same category or niche, then it would look a little bit spammy to search engines.
Like if you have something like ‘cheapseoservices.com’ or ‘seoservices4u.com’ or any other thing which looks to be the same to the bots, then you may have a problem and can actually land up in the spam list of Google.
But on the other hand if you have valid reason to do so like, if you have many other country specific domains, meaning different domains for different countries and you would like to get them all to one single domain, you can actually do that.
But that too with a trick, Matt Cutts suggests that don’t put everything on the footer side but try to develop a different drop down menu or something that actually displays the different version of the site.
My take on this
Matt knows about this but if you have different sections on your blog for everything and give a different link there (obviously for your other domain), that actually serves the purpose of being there, then I don’t think Search engines will have a problem.
Moreover I don’t think many of the bloggers have more than 2-4 blogs and I don’t think they will interlink them as they will definitely be of different category or niche, coz if they belonged to only on category – why would they even buy different domains for them.
And also for SEO professional, if they are building hundreds of sites for their customers, then I don’t think their customers would like to cluster their links on one page, as it could also feel like a link farm.
Video for matt cuts
Other than that:
You are my most valuable readers and if you have any more suggestions to that, I have all ears and eyes on the comment section, you can write your views, reviews or whatever you like but please don’t add spammy websites, I have to review and delete them and that is definitely a tedious procedure.