Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Canon SX120 IS and Sony NEX-3 side-by-side from the front, back and top in their relative dimensions. Canon SX120 IS has external dimensions of 111 x 71 x 45 mm (4.37 x 2.8 x 1.77″) and weighs 285 g (0.63 lb / 10.05 oz) (including batteries). Sony NEX-3 has external dimensions of 117 x 62 x 33 mm (4.61 x 2.44 x 1.3″) and weighs 297 g (0.65 lb / 10.48 oz) (including batteries).
Below you can see the front view size comparison of Canon SX120 IS and Sony NEX-3. Sony NEX-3 is 9mm shorter and 12mm thinner than Canon SX120 IS but it is also 6mm wider. As you can tell, actually this is not a fair size comparison since Canon SX120 IS has a built-in lens but Sony NEX-3 doesn't. Once you put a lens on NEX-3, its thickness will increase significantly.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Canon SX120 IS is 12g lighter than the Sony NEX-3 but we don't think this will make a significant difference.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on NEX-3, the total kit will weigh much higher.
Unfortunately neither Canon PowerShot SX120 IS nor Sony Alpha NEX-3 provides any type of weather sealing in their body, so you have to give extra care especially when you are shooting outdoors. If weather sealing is a must-have feature for you, check these sections: Top Compact Cameras with Weather Sealing Top Mirrorless Cameras with Weather Sealing
LCD Screen Size and Features
Canon SX120 IS and Sony NEX-3's LCD screens has the same diagonal size of 3".
On the other hand, Sony NEX-3 features a Tilting screen
where you can change the angle of the screen to make it easier to shoot from waist or over the head levels whereas the Canon SX120 IS has a fixed type screen which provides less flexibility in shooting positions compared to NEX-3.