Ask HN: Do you connect with unknown people on LinkedIn?

I do. If they write a proper note stating their reason for connecting.

Yes. Often recruiters ask me to connect with them and occasionally I found a nice job that way.

You can always remove connections. Having a larger network won't hurt you. If it seems completely random or an accident, don't do it. But consider - "could knowing this person in 4 years be a good thing?" Almost always the answer is yes.

Usually, but with a few exceptions. If a random person tries to connect with me, and one (or more) of a few conditions is true, I almost always accept. Those conditions would be things like "We have a lot of connections in common already", "they include a note explaining why they want to connect", "it's apparent from their profile that we have common interests that justify connecting", etc.

OTOH, a few "red flags" almost always cause me to decline. Some of those are "the profile looks obviously fake" (these are the ones where the picture is a beautiful blonde woman, and her profile shows no education history, one job with a generic description like "retail" and they have like 5 total connections, and none in common), or "some guy in another part of the world, in a completely different industry, with no obvious sign why there would be any mutual interests, and there's no note explaining why he wants to connect", etc.

That said, if one of you sends me a connection request saying "Hey, this is 'soandso' from HN" then I would almost always accept that.

Some people curate their connections. Others don't.

If curating is providing a benefit, continue. If not, then there's less reason to do it. Me, I decided to pretend to have lots of business friends years ago, but I spend so little time on the site that their status updates don't create much noise.

I don't find much value in the activity.

LinkedIn is a social networking site for business professionals. In fact, it is heavily used by recruiters and employers to source candidates for employment. So, don't be surprised if you've seen people in Sales or Recruitment who are trying to connect with you.

In regards to your question about the positives and negatives of LinkedIn connections - let me provide you some:

1.) Career Networking - We can all benefit from building a network and LinkedIn can serve that role.

2.) Identification - LinkedIn is not going to work for you if you don’t identify yourself. However, if confidentiality is a concern, and if you are trying to stay anonymous, just be careful to connect with only people you know well.

3.) Search Engine Exposure - You can connect your blogs and other social networks to LinkedIn. Your LinkedIn statuses can be updated when posting to one of those places, providing the opportunity for greater network connections.

4.) Job Hunting - Let say that you are looking for a job, but you are currently employed and you don't want to jeopardize your current position. Be strategic and don’t announce to your connections that you are searching for a job. You can still do your job search confidential by not providing your company's email and phone number.