Lol, I was trying to figure out what you meant by cell-based. I wondered if maybe there was a new thing of which I wasn't aware, but I figured out that you still meant raster/vector. Both Photoshop and SAI are actually raster programs, meaning colors are created pixel by pixel. I know SAI says it has a vector tool thing but technically so does Photoshop, but they are not "true" vector programs. Programs such as Flash and Illustrator are vector-based; meaning, instead of creating images pixel by pixel, images are created by using algorithms to make complete shapes. This makes it useful when creating promotional and marketing materials, logos, graphic design, etc.
Vector programs allow you to scale your shapes and images without losing information (pixels). However, they cannot use as robust a color palette as a raster image (also known as a bitmap). Vectors are better with solid colors or smooth gradients.
Because raster programs create images by pixel, they can have a large array of color in single image or "shape." Pixels contain a lot of information and so affect file size. They also cannot retain the information when reducing or enlarging an image as a vector can. Enlarging an image will cause it to become blurry or distorted. (Tip: When drawing, painting, etc. in a raster program, start with a larger canvas/image and reduce the size of the image when you're done. Your image will come out looking cleaner and crisper.)
I know a few artists who use a combination of vector and raster programs. One in particular starts all of her pieces in Flash and then imports them into Photoshop to add textures, filters, and additional touch-ups.
Also, if you'd perhaps like to get your feet wet with animations, both Photoshop and Flash have these capabilities.
250
200
200
