In my opinion, unless you like taking Polaroid snaps, you will be shooting in raw format. So you will need some kind of raw processing (development) software. Here are a few:
Capture One
Phase One
www.phaseone.com
In my opinion (but not in everyone else’s!) this is the best processing (“development”) software. It takes some time understanding the user interface and understanding how all controls work but once that done, it is a very fast and efficient tool that gives excellent results. And they have a very good user forum. They have different packages (LE, Pro…). It used to be referred to as C1 but I believe they had a trademark issue with that.
Photoshop Camera Raw
Adobe
www.adobe.com/products/photoshop/cameraraw.html
Often referred to in jargon as ACR (Adobe Camera Raw) it works as an integral part of Photoshop (but you might need to download it and install the latest version separately from the PS program). Some people swear by this only but I find it slower to work with
RawShooter
Pixmantec
www.pixmantec.com
This Danish company was created by some “defectors” from Phase One who wanted to do, in their opinion, a better raw processor. They did one version that was called RawShooter Essentials (RSE for short), which was free (yes, entirely free), and then they did a Pro (upgrade) version that was not free. And then they ware bought by Adobe who wants to integrate some of their technologies in its own products (e.g. Lightroom?). I found RSE to be very fast in some respects (e.g. in producing screen previews) and it also has some clever image enhancement functions, but in the I decided against it because I did not quite like the colours it produced. But I still use RSE for browsing and editing (sorting out bad ones) raw files. I find it very fast to work with for that specific purpose. They still have the software available on their site which strikes me as curious. But take the opportunity to download the free version while it’s there. It’s useful.
Adobe Lightroom
Adobe
labs.adobe.com/technologies/lightroom/
The new (not even released as a product yet, but free to try in beta version) is supposed to be “built from the ground up by photographers, for photographers…” etc to take care of the full digital workflow. What I have seen of it, that is not quite the case. Rather, it seems to be a fusion of a cataloguing software and a development software (as if you packaged together Extensis Portfolio and Photoshop in one app). It remains to be seen if it is really industrial grade and suitable for a professional workflow.
Aperture
Apple
www.apple.com/aperture/
Have not tried this either (in particular since I don’t use Macs). It too (like Lightroom from Adobe) claims to be the ultimate solution for professional photo management applications. Who knows?
Bibble
Bibble Labs
www.bibblelabs.com
Some swear by it. I have not used it.