In the roughly four months since its debut the iPad has sold in excess of 3 million units and has defined an entire category of devices. Apple’s monstrous success has every competitor scrambling to play catch up. So far Apple has had the tablet category all to themselves, but for how much longer?

Though Apple was the first company to hit a home run in the tablet category that doesn’t necessarily mean that everyone in the market for a tablet will jump on board with the iPad. Forrester has released a research report that shows that while 27 million Americans will be in the market for a tablet in the next year, they are not necessarily looking at the iPad. Only 3.8% of these future buyers said they were going to buy an iPad. Meaning there is a huge target market for Apple’s competitors to hit.

So who is throwing their hat in the ring? Just about everyone. The Technologizer did a great article on what they have dubbed “iPadversaries” and listed 32 potential competitor devices. Some devices from relatively unknown companies and some from the big names like Google, HTC, HP, Dell, Windows and Blackberry.

Despite, all of this activity and this potential flurry of tablet devices hitting the market, I don’t imagine Apple is too concerned. Apple is not a company known to rest on their laurels. Despite the iPad being a huge seller we all know that Steve Jobs and company are hard at work behind the scenes on improving the iPad. This means that competitors not only have to bring a tablet device to the market that is better than the iPad is now, they have to have a device that’s better than the iPad 2 is going to be. And that won’t be easy.

So which of these devices are you most looking forward to? Are you putting off buying an iPad so you can wait and test out the competition first?