With improved cell phone cameras, point-and-shoot cameras are not required: As technology progresses, maybe this will come true in the future. But as of now, a mid-range point-and-shoot camera will outclass any production cell phone camera — 5MP sensors, 3x optical zoom and Carl Zeiss lens on expensive mobile phones notwithstanding. The reasons are pretty simple — the limited size and weight constraints in mobile phones impose a design restriction for putting in a capable camera. Remember that, an auto-focus camera is an electro-mechanical device that does take up some space and requires precision. In bright light, a really expensive camera phone will produce good results, but come low light and its small sensor and limited flash capability start acting up. But, it won't be long before camera phones evolve to a level where they can do nearly everything a simple dedicated point-and-shoot camera can.
HD camcorders record higher quality video than normal ones: If the only factor for video quality were to be the resolution, this statement would have been true. But, it is not. Similar to how a higher mega pixel number does not imply a better digital still camera. In a camera or camcorder, video quality is determined mostly by the optical properties of the lens, the noise levels of the sensor and its dynamic range and the kind of compression used. A HD (High Definition) or SD (Standard Definition) only specifies how large the video is going to look on a screen, but does not indicate how good or bad its quality will be. Manufactures are increasingly flaunting the 'HD' capability but entry level HD camcorders offer no significant quality improvements over non-HD models. In fact, an advanced standard definition model is in many cases better than a cheaper HD one.
A camera with higher ISO is better than one with a lesser number: In theory, higher sensor sensitivity, indicated by the ISO figure makes for better low light photography. With point-and-shoot cameras however, using a very high ISO number leads to extremely high noise in the images. So much so that if you use the ISO 1600 that some small cameras have, the resulting image will be so noisy that it is hardly usable. If all other features are equal, a higher ISO feature alone is not worth paying a heavy price for.
