Chris M. share's some images of his Cineroid EVF which I believe is the first EVF out on the market. We're still waiting for Zacuto and RedRock Micro to release their version. If you're that impatient type that needs an EVF now, there's a limited amount of these Cineroid things you can grab over at HotRodCameras.com, where you'll find more information about all the questions you might have.
Shortly after RedRock Micro announced their EVF - Electronic View Finder for DSLR's, Zacuto now has a complete web page and video showcasing their product. Actually they've gone as far as a complete domain name @ ZFinderEVF.com. It's still up in the air if RedRock Micro has an actual working version, but from the images that were submitted, it doesn't look like a finished product. Actually in this Video (above), Zacuto is also just showing a 3D model, so take this as just another announcement and not an actual product (yet).
Marketing is always ahead of technology and some people are speculating that the announcements were aimed just to be the first. Hopefully the products are released soon, as we've seen some bad turnouts on early announcements for products that never seem to make it to market or experience long delays. Personally it's all exciting, but I don't know if consumers really care who's first to announce what, it's more about first actual availability and pricing. I'd even take my chances on a no-name brand EVF if the resolution was adequate.
Redrock Micro is stated to come in around $600 dollars, and the Zacuto EVF just under $800. If i'm correct, you'll still need a Z-Finder to use with the EVF bumping that price up a few hundred more. This is something many DSLR shooters have been looking for and I feel they'll be set to grab whatever becomes available early on. Under those brand names, they'll both be well made products, but since Zacuto's will be several hundred more (including Z-Finder Loupe), time to market is what's really going to set the pace on EVF sales.
Another option would be going with the smaller 5" LCD monitors such as the Marshall V-LCD50-HDMI. Unlike the EVF's announced, the Marshall Monitor has additional features for setting proper exposure. I guess if you really wanted magnification for the LCD, you could just make a DIY loupe using a Macro Close Up FIlter and a box.