I have both. I have had Elements for a long time, and Lightroom for three years or so. (I also have Photoshop, since I bought the photographer's CC offering).
The key to thinking about Lightroom is that it is a workflow application. It allows you to manage your photos, process them, Print them and publish them - all within one product with a consistent interface throughout.
The controls and workflow are exactly the same, whether you are working with jpegs, RAW or a mixture.
As I've got to know the product better, and Lightroom itself has developed, I can do almost everything I need in Lightroom. It does not just offer global adjustments. Whilst it does not have the sophisticated mapping of the Photoshop products, a lot can be accomplished with its filters and brushes.
There are some things it doesn't do. If you want to combine images (other than hdr and panorama) it doesn't. Nor is it the place to create special effects.
One slightly arcane point. Lightroom is not a RAW converter, it is a RAW interpreter. Your RAW images stay RAW until you move them outside of Lightroom.
So it depends on your needs. If Lightroom can do what you need, I can pretty much guarantee you can do it more quickly in Lightroom than in Elements.
Finally, sorry about the long post, if I wanted something to do the sorts of things Elements can, but didn't want to tackle Photoshop, I would choose On1's Photo 10 over Elements every time (actually, I have!)
If you want want to get a quick start with Lightroom, try Victoria Bampton's free quick start guide:
http://www.lightroomqueen.com
Cheers,
Dave