Hands down it’s Photoshop. You can certainly get away with PS Elements 6 until you reach a point where you see the need for the larger (CS3) version. $90 or so vs. $600 or so.

Lightroom is great for what it does. But it doesn’t offer features like Layers – which are pretty important to most serious photographers.

Photoshop is NOT designed primarily for Graphic Designers. It is first and foremost a program that performs all the development and image adjustment functions of the traditional darkroom. And it simply does these basics better than any other software.

After that – and only after that – does it offer the added features that are of use to graphic designers.

Tortuga Tom, you can merge to HDR in Photoshop.

Depending on your needs, Adobe Photoshop may be more powerful than you need (and as Tortuga Tom mentioned, is more geared towards graphic artists).

You might want to try Adobe Photoshop Lightroom, which is designed specifically for photographers.

Photoshop is actually designed for graphic artists, not photographers. Not to say it’s better or worse than any other. I use Photoshop. I also use PaintShop Pro. And Picture Window Pro. And Photomatix. Some are better (read: more effcient, or faster) to use than others. Some have features others’ don’t. Depends on what you’re doing. Simple tweaks, I use PaintShop. If I need to shed distractions, or do effects, Photo Shop. HDR requires Photomatix. Up-rezzing, I use Picture Window Pro.

Photoshop does have some some tech difficulties sometimes, but it is by far the best.

Photoshop is far and away the de facto standard for photo editing. Not to say Corel makes bad products, it’s just that Photoshop is the standard.