the Tamron 18-270mm PZD seems good. Got a friend who tested it at a shop with his canon body..what I see from his lcd, it was pretty good for the range. you should read up reviews on canon 18-200 should you be thinking of getting it.
1. Depends on your budget, how much do you want to spend?
2. Personally, I started with 18-55. Came with my 40D as kit. Too dark and was a little disappointed.
3. My all time favourite, EFS 17-55 f/2.8.
4. But this depends on your shooting style.
Ask yourself if you ever wished you wanted a wider field of view, if you needed a longer reach, if you wanted to play around with different perspectives, if you needed a larger aperture for subject isolation or low light shooting. The 18-200 is a lens that covers a lot of range and does offer you different perspective distortions (wide and tele), but it does not offer much subject isolation compared to a fast aperture lens. I seldom shoot tele but I want good subject isolation so a general purpose lens for me would be a lens in the 16/17-50/55 f2.8 range. Some people never shoot wide so a general purpose lens for them may be a 50 or 85 prime, or even a 70-200 f2.8
So it really depends on how you shoot (less so about what you shoot), find out what your current lens/lenses are lacking in terms of catering to your own shooting style. Don't just blindly buy a lens just because it has a large aperture or if it has a longer reach, make sure you really use those features before you decide what you want to buy.
BBB trend will not end for this poisonous hobby to begin with.
I feel that it will give the user a wider range of focal length to shoot till another need arises ?
I often have the "****.... this is the "zoom" I can go with my old 18-55mm"