The REU at Oregon State University notified me that they've received every necessary piece of my application, except my two letters of recommendation (at least one is either being filled out and will be submitted tomorrow, or it already has been submitted; the other, well - not sure yet). Every article of the application for Oregon State's REU is 15 February.
Also, I need to submit my unofficial (and updated) transcript to the REU at Texas A&M University. I meant to do this weeks ago, but I thought it would be in my best interest for my MATH199 course to appear on my transcript beforehand. Now that it is updated, I can submit the last, crucial piece of my REU application to College Station, TX.
I believe that the notification of acceptance (or denial) e-mails and letters should begin to arrive as early as late February - early to mid-March is more likely.