Identical to what ?
Identical does have a very precise meaning and is always relative to something ..
This monitor (a) 22" def is 1600x900
The one next to (b) it 22" is 1680x1050
The one twinned ( dual screen set up ) with (b) (c) is a 22" 1680x1050.
The 3 other machines in the room are all on separate monitors at 22" 1680x1050
The 32" HD TV in the corner is a 720p
Our other TV is a full HD 1080p
Both are connected to the web and to media centres and games consoles.
Upstairs we have 3 22" monitors 1680x1050 attached to 3 machines..and 1 720p HD TV,' again connected to games consoles and web).
Not all the computors are connected to the web..those which run windows are not ;-)..
Many here ( because we work with the web ) will have similar setups to the above..but we are not our average customer or visitor..
The average person's ( webmasters do not buy average laptops ) laptop is much closer to the 720p def than it is to the above monitor definitions.
iphone4 is 960x640
ipad2 is 1024 x 768..
The latter two are much closer to the 720 HD TV def than they are to monitor def..design for them ( what the vast majority of your average people have )..and it works for the rest..except for those tiny few who surf at fullscreen on monitors..or who surf at fullscreen on full HD TVs.
You either see that designing for what you have and what you do, and how you act, instead of what your customers and visitors, have, and do, and act, is an error, or you don't.
And if you don't?.. then thats my gain ;-)