I forgot to mention how I batch resized images from some Timelapses we've been working on since Photoshop CS4 won't open .NEFs from a Nikon D7000.
Use Preview. Yup.
0. Launch Preview and hit Command + (comma) to open it's preferences and under General make sure either "Open all files in one window" or "Open groups of files in the same window" are ticked. This is important.
1. Drag the folder containing all the images for the Timelapse onto Preview's icon.
2. After Preview opens all the images in one window hit Command + A to highlight them all.
3. Goto Tools > Adjust Size… and type in the resize you want or need.
4. Hit Okay, and wait for Preview to do it's thing.
5. Hit either "Save All…" or "Save As…" as per your need.