Larry is giving you the facts s they are if you consider the info he is giving you, you will see it clearer if you hang on a while it will come to and make much more sense.
Unfortunately it would be better to have reading the other way or have them both ways so that an image at 100% @ 300ppi is reported as 100%.
However when placing this in a document that will be pixel based for the web you should have the choice of converting the file to 72 ppi at the current dimension or allowing it to be displayed at the default resolution of 72 ppi at full pixel dimension.
Although other users might have different preference. I wonder?
At any rate you should mark Larry's answers as the answer so other who query about this can find it, it comes up so often that marking it would be helpful for other users.
So the information in the link palette is showing me the percentage of the size at 72 dpi. This unfortunately gets very confusing when you are rescaling the image in illustrator while thinking it was coming in at 100%.
What is the point of the link information in the link palette if Illustrator is showing the file at different size versus what it actually is in photoshop? Why is it that a 300 dpi psd file shows at 100% and a 300 dpi tiff does not?
It does not seem that you are relating to this mechanism.
First you are definitely not using dpi, you are using ppi. There is a big difference in the two, so unless you are clear on this then you will not understand it.
Dpi is dot per inch there are no dots per inch in your file as far as the file size is concerned.
Dpi is the print specification for the coarseness of the print screen.
Ppi is the file dimension in pixels so if it is displayed at 72 ppi as in illustrator but is actually 300 ppi in reality it is being displayed at 24% of the 300 ppi file size at the same print dimension.
This dimension percentage only refers to the display ratio at full dimension to the actual pixel dimesion.
It is just about the presentation in AI that is all there really is to it.
If you want to check that you file is the correct dimension by the correct ppi then look in the document info panel for that for embedded or linked files.
BTW if the psd and the tiff file is the same dimension and resolution then they will display at the same percentage so somthing is wrong if they are not displaying that wy.
I hope this helps
BTW I have to admit that i too was very confused by this as well until I visited the Photoshop and Illustrator forum.
So there is good help here.
Gary Newman and James Talmage both had better explanations of this and after rereading their post one day I realize that my thinking was on the press and not on the computer as well as Chris Cox from Adobe on the Photoshop Forum and the late Bruce Fraser as well.