Photo Copyright: Wesley Miller
The problem with any kind of art is that a person can easily find themselves in a rut. If you're uninspired for whatever reason but still feel the need to create, you'll resort to what you know. Comfort food for your artistic soul, as it were.
For some, that is fine. Artists go through phases. Depression can drive a person to create several works with seriously dark undertones, joy can cause a person to create several works with bright, sunny flowers all over. But that's not the issue.
The issue is overuse of a technique to a point that almost no photo taken by that person is unique. One example is taking a photo of a car at an angle. Yes, many professional photographers use this technique to accent an angle or body line in the vehicle that makes it truly unique. This is usually used in combination with creative lighting and a simple background to help further accent said feature. However, using this technique with just any old car with a busy background can result in a photo that simply disorients your audience as they crane their neck trying to figure out what exactly it is you photographed. Another example is overuse of "canned" effects. Say a faux-vignetted border. This technique seems to stem from the "Holga" and similar cameras who's cheap construction often led to strong vignettes as well as other photographic anomalies. The problem is that your D40 or EOS Rebel is not a Holga. It is a far superior piece of equipment. These vignettes, when used on an appropriate image can lend that "Holga-esque" quality but on just any image it tends to lead to a loss of detail or just total distraction from the overall image.
Once again, this comes back to the fact that professional grade equipment is becoming affordable to everyone and this is causing "everyone" to think that picking up a D300 suddenly makes them a pro-shooter. But let's not be hasty to cast judgement. There are some who for whatever reason decide one day to go buy a camera, have some money to spare, plunk it down on a high-end dSLR and end up taking some absolutely stunning shots, having never touched a shutter button in their life. The problem is that in their zest for making a name for themselves, they proceed to ruin these gorgeous images by applying that vignette or whatever generic effect.
This does not make a name for an artist. Applying a pre-made filter to an image is not a unique style. Michael Orton would be a good example of someone who used a certain technique a fair amount in his work, but this was his own creation. It as unique to him. It has been used successfully by other photographers since, but again, it wasn't just some pre-made, point and click filter that was applied to the image.
To sum up, when you take that magnificent photo of the fall colors or want to get a really cool shot of your tricked out car, think very hard about how you want it to turn out before you press the button. If people are going to put a kink in their neck trying to see just how sharp your ride is, maybe level that camera out and leverage depth of field or try another backdrop, move in closer, anything. And before you apply that vignette, have a look at the photo as it stands. Bet it looks just great as it is and if you really, just REALLY have to make it stand out from the pack, just expand your canvas in Photoshop a bit and add a small border for that "matted" look.