Fashions change in all walks of life, and its no different in photography.
Imaging software such as Adobe Photoshop, Lightroom, Aperture and others allow photographers to process their pictures beyond all recognition, tweaking colours and adding effects without destroying the original image file. This allows experimentation, which is not a bad thing.
But its bad when people get carried away and try to save bad photography by overdoing it at the processing stage. You've only got to spend a bit of time on photo sharing sites like Flickr to see some truly horrendous examples of overdoing it.
The current fashions in photo processing seem to be "HDR" and "Vintage". HDR stands for High Dynamic Range and is a process which allows photographs to show much more detail in highlights and shadows than normal by combining multiple exposures into one. It can be done well, but it rarely is. The other current fad is the "vintage" look - faded colours and scratchy textures to make pictures look old. Again, its done badly more often than well.
I like to think my pictures have a definite style, but I'm aiming for pictures that look like traditional hand-printed darkroom prints. Black and white images that have been dodged and burned in the same way a wet darkroom print would be made. And colour images that accurately represent the actual colour of the things in the photograph.
I know how to do all the fancy, fashionable image processing that's all the rage at the moment. I choose not too.
I don't want people to look at my wedding albums in 5, 10 or 50 years time and laugh at the "unfashionable" look of the photographs.
The content of the photograph is the most important thing. Good photography never goes out of fashion.