One of the nicest new features of InDesign CS4 is the ability to automatically place multiple images at once, arranged neatly in a grid of frames automatically created to your specifications. Here's how:
1. With nothing selected on your page, choose File > Place, and select multiple images by clicking on one image, and then command-clicking (Mac) or ctrl-clicking (Windows) on subsequent images.
2. Click the Open button. InDesign will import all the images you selected, and then display the "place cursor" with a number showing how many images you've imported.
3. Hold down command-shift (Mac) or ctrl-shift (Windows), and drag out a rectangle. You will see a grid of frames appear. Don't release the mouse button, but you can now release the command/ctrl-shift keys.
4. Now, while continuing to hold the mouse button down, you can adjust the number of rows and columns using the cursor (arrow) keys on the keyboard. The up/down arrows increase/decrease the number of rows in the grid, and the right/left arrows increase/decrease the number of columns in the grid.
Again, while continuing to hold the mouse button you can adjust the space between the rows and columns using shift+the cursor keys on the keyboard. Shift + the up/down arrows increases/decreases the vertical space between rows, and shift + the right/left arrows increases/decreases the horizontal space between columns.
5. Release the mouse button, and a precise grid of frames will be created, with an image placed in each frame.
Only as many frames as you have images selected will be created. In other words, no empty frames will be created. So if you've dragged out a 10 x 10 grid, but only have 15 images selected, only 15 frames will be created, not 100.
Conversely, if you have more images selected than the number of frames you specified in your grid, after the first grid is created, you will see another "place cursor", and then you can repeat steps 3-5 to create a second grid.