Can Google distinguish between relevant and spam blog commets?

Blog comment links are still links on a webpage (assumes a followed link which is easy to find), they can still rank pages just the same as any in content link.

There's still problems with the average blog comment links, like comment/pages hit by massive spam (100's of irrelevant links per page).

IMO comment/links are a temporary ranking solution & should be expected to generate a Google slap, might not happen but should be expected (disposable sites). People building those types of links should at least be realistic.

I have a feeling the algorithm is slowly changing on some fronts.

Let's look at spammy links by definition:

- blog comments
- web directories
- social bookmarks

What do these have in common:

- Lots of irrelevant links on the very same page, though not will all platforms of course where you first have to click the title that leads to an inner page and links from there to the client site.

Anyway, if they figure out that footprint, instead of going after unique footprints like "Powered by Pligg" or "Leave a comment...." type of things they'll be able to make a clear difference between a spammed blog with tons of links to different subjects then a heavily moderated blog where everyone links out to the same type of sites (think of popular IM blogs like Quicksprout where most of the links point at other IM related sites) instead of Viagra, Payday Loans and what not.

With such footprint they can identify more types of spammy links, think of PBN links with dozens of OBL on the homepage to all kinds of sites.

I think this already happened during Penguin 3.0 though most link sellers won't admit it but keep yelling business as usual while it's clear when you read the thread on BHW that there are tons of people penalized that mostly had these type of links.

Personally I used to run such network and I did have quite a few clients tank, mostly the ones that used my service for a longer amount of time. Now I adjusted my network, and even took one of my networks down (a weak PR2 one) and we are already seeing some recoveries, maybe cause Google is still rolling out (personally I don't think it should take weeks to roll out but just in a matter of days) so perhaps they are re-running the refreshes in a modified way to test stuff. That explains the jumpings up and down.

Anyway the sites that recovered can be counted on 1 hand so nothing scientific about it, could have to do with other factors but it doesn't take away my initial point of links next to irrelevant links. Hence that I restructured my service completely and testing different things like in that public case study I posted.

All adjustments are based on common sense and on proven strategies from people that didn't tank, eg analyzing crappy sites that still ranked despite unnatural link profiles, just executed in different ways.