No previous versions required
Adobe has extended their Photoshop CC/Lightroom 5 deal until December 8, 2013. I'm assuming the extension is due to the positive response to the pricing and requirements.
You can get both Photoshop CC & Lightroom 5 for $9.99/mth without owning a previous version of Creative Suite or Photoshop.
I have personally signed up for this promotion and I know I'll be happy.
Visit Adobe for more information