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 Olympus XZ-10 and Panasonic ZS20 side-by-side from the front, back and top in their relative dimensions. Olympus XZ-10 has external dimensions of 102 x 61 x 34 mm (4.03 x 2.41 x 1.35″) and weighs 221 g (0.49 lb / 7.80 oz) (including batteries). Panasonic ZS20 has external dimensions of 105 x 59 x 28 mm (4.13 x 2.32 x 1.1″) and weighs 206 g (0.45 lb / 7.27 oz) (including batteries).
Below you can see the front view size comparison of Olympus XZ-10 and Panasonic ZS20. Panasonic ZS20 is 2mm shorter and 6mm thinner than Olympus XZ-10 but it is also 3mm wider.
Here is the back view size comparison of Olympus XZ-10 and Panasonic ZS20.
Now lets look at the top view comparison of Olympus XZ-10 and Panasonic ZS20.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Panasonic ZS20 is 15g lighter than the Olympus XZ-10 but we don't think this will make a significant difference.
Unfortunately neither Olympus Stylus XZ-10 nor Panasonic Lumix DMC-ZS20 (Lumix DMC-TZ30) 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
LCD Screen Size and Features
Olympus XZ-10 and Panasonic ZS20's LCD screens has the same diagonal size of 3".
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.