Am a newbie in this field and am not a canon or a sony user, but I am a proud DSLR user

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Before I bought my first DSLR, I have done quite a lot of research and have remembered the first rule which I still have been using and applying...
"It is not the camera, it is the shooter."
Here is the review of both A200 and 1000D from dpreview:
http://www.dpreview.com/reviews/SonyDSLRA200/page31.asp
http://www.dpreview.com/reviews/CanonEOS1000D/page34.asp
They have both Highly Recommended ratings, so, whichever camera you settle, you will not go wrong.
If you also do browse this very helpful website, it shows so many happy users for both A200 and 1000D.
My suggestion to the TS:
Get used on the camera you have right now, spend some time with it and learn how to go around its negative side. Each of these cameras have their own advantages and disadvantages. If you think the advantage and disadvantage of A200 is right for you, then go for it and learn how to overcome the negative side of it.
For example, one of the cons in 1000D is
"Average automatic white balance performance, still very poor under incandescent light"
However, this can definitely be compensated using many method, i.e. setting the WB manually using custom, or shoot raw and do PP.
One of the cons for A200 is
"Poor white balance performance in artificial light"
Same solution as above.
So, I'd like to suggest to the TS not to be disappointed with what you have right now, but try and overcome the negative side of it. Even if you buy a high end camera (Canon 5D MarkII or Nikon D3, or whatever) ... there will always be negative side on it. You just have to learn how to get around it.
Good example.
I was shooting in Kentridge Park for sunset couple of days ago. An older guy with Nikon D3 was shooting at the same time. I only have a D5000. We compared our shots and he actually liked my shots better. I showed him my settings... and let him borrowed my ND filter :bsmilie: .... and he became happy with his shots on the sunset. He then realizes... there are lots of ways and means to shot a subject, it is how the photographer captures the subject. And he will buy an ND filter soonest

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Hope this helps.