Lorenzo Puleo has released DiapoSheet 1.0 for Mac OS X (10.6 or higher). It costs US$24.99 and available worldwide exclusively through the App Store in the Photography category (http://tinyurl.com/crxsc7p).

DiapoSheet lets you lay out your photos with metadata-exif and get a contact sheet PDF file. Drag a folder containing images onto the DiapoSheet window and you are done. You can change the number of rows and columns, their gaps, the margins, the page size and format, add your custom logo and company description, your watermark, display the metadata-exif with your favorite font, color and label.

You can then export your document to PDF, TIFF, PNG, JPG at the resolution of your choice. You can select the resolution of the images even when exporting to PDF.