I used to be able to type Links: domainnamehere.com and it said over 2000 but now I have ~600. What happened?
the 'link:' operater is not really very accurate, a large portion of links are usually hidden. To get better stats open up a Google Webmasters Account and verify your site with them (all free btw). Then navigate to Links > external links. This should give you a more accurate picture.
This is true... but even if it were not... why are you worried, if you did lose all those links and you didn't lose your rankings then what good were they? We are so focused on PR and links I think we forget we are really after rankings not either of them.
Good point. A lot of people lose focus of the ultimate goal. They get so hung up on PR and links instead. Also try checking your links on Yahoo. They tend to show a much larger percentage of your actual links.
...also - you may have lost those links because the site(s) they came from went down/ got delisted/ - or if they're forum links, they might simply have lapsed after time.
Google links command is not based on value, it is just a small quantity of the links you have, not based on any value in the links or any other factor.
That's not the point. He may have lost links that he had before. Sites that have links do get de-indexed and/or lapse.
If you have been doing Article or Press Release submissions, then these "links" get archived. Or moved to a new location. You will find that they will not be archived. This is why they are called "Temporary" links.
Link : domainname just shows the sites that have your domain name on them, not necessarily backlinks so maybe those sites removed your domain name from them. If you want to see accurate links there shouldn't be a space
No if he lost any links he would have lost rankings as well... don't tell me he can lose a thousand links and not lose any rankings. The idea that 1000 links would disappear overnight is really ridiculous.