Size and weight are big decision factors when you are trying to find the ideal camera for your needs.
In this section, we are going to illustrate the Olympus SP-600 UZ and Panasonic GX1 side-by-side from the front, back and top in their relative dimensions. Olympus SP-600 UZ has external dimensions of 110 x 90 x 91 mm (4.33 x 3.54 x 3.58″) and weighs 455 g (1.00 lb / 16.05 oz) (including batteries). Panasonic GX1 has external dimensions of 116 x 68 x 39 mm (4.57 x 2.68 x 1.54″) and weighs 318 g (0.70 lb / 11.22 oz) (including batteries).
Below you can see the front-view size comparison of the Olympus SP-600 UZ and the Panasonic GX1. Panasonic GX1 is 22mm shorter and 52mm thinner than Olympus SP-600 UZ but it is also 6mm wider. As you can tell, actually this is not a fair size comparison since Olympus SP-600 UZ has a built-in lens but Panasonic GX1 doesn't. Once you put a lens on GX1, its thickness will increase significantly.
Here is the back view size comparison of the Olympus SP-600 UZ and Panasonic GX1.
Now lets look at the top view comparison of Olympus SP-600 UZ and Panasonic GX1.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic GX1 is significantly lighter (137g ) than the Olympus SP-600 UZ which may become a big advantage especially on long walking trips.
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 GX1, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Olympus SP-600 UZ nor Panasonic Lumix DMC-GX1 provides any type of weather sealing in their bodies, 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
Panasonic GX1's 3.00" LCD screen is slightly larger than Olympus SP-600 UZ's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.