Mac Mini i7 or iMac i7?

-I want to buy upgrade from a white unibody macbook to either the Mac Mini i7 1000$ or the iMac 21.5 i7 1700$ If i get the mac mini i'll buy it directly, but if I get the iMac, ill wait until September. I want a fast machine that handles multitasking easily and supports editing photos and videos like a breeze. I do not want it to slow down at all.Mac mini + solid state drive option

You don't need a high end computer to edit video and photos at fast pace. i7 processors quad core is great for fast processing and multitasking, fast operating system like OSX and good editing software is what apple have on all their computers, but make sure it's 4gb of ram or more. The only thing that slows down is the hard drive, and that's what SSD comes in, if you're willing to spend extra option for solid state drive it will make whole lot of different when comes to speed. if you're worrying about storage there's (750GB Serial ATA Drive + 256 Solid State Drive) option or just buy a external hard drive. And it's still cheaper than getting a imac 2.1 for $1700, the rest of money can get you a really good monitor.