Using Software against TOS?

I think it has to do with the specific task being automated and with the intent of the automation.

Google has said all along that it doesn't sanction tactics that are done purely to game the system, automated or manual.

When MFA software was riding high, the Google databases were being stuffed with junky sites full of nonsense and stolen content, with the sole intention of being good enough to draw clicks and so bad that visitors clicked ads to leave.

When they started losing users and advertisers, they cracked down on those auto-generated sites.

I think the same thing will happen, or is already happening, with spammy, junky autoblogs. (I'm not slamming autoblogging, keep reading...) These junk blogs are just the next generation of junky MFA sites.

That's the kind of automation that will get you de-listed or banned.

On the other hand, take a task like directory submission. The highly educated propellerheads (a term of affection) expect owners of new sites to want to spread the word far and wide. They also know that filling out and submitting forms is one of those tasks actually suited to automation. So if the spiders see a few hundred or a few thousand links suddenly appear on directory sites, it's no big deal.

Earlier, I mentioned auto-blogging.

Entering selected search terms and compiling the results, as well as entering data in a database on a schedule, are both the same kind of repetitive tasks well-suited to automation. So using the available tools to ethically collect content is not a big deal. Nor is using a tool to post on a schedule.

Where the problem comes in is when the intent is to benefit unfairly from the use of tools, like aggregating content and then stripping out the links and replacing them with your own. Or spamming blogs with garbage comments to artificially inflate the number of links to a given page to gain an artificially high search position. Stuff like this will get you de-indexed and banned.