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 FujiFilm S2800HD and Olympus E-P3 side-by-side from the front, back and top in their relative dimensions. FujiFilm S2800HD has external dimensions of 110 x 74 x 82 mm (4.33 x 2.91 x 3.23″) and weighs 437 g (0.96 lb / 15.41 oz) (including batteries). Olympus E-P3 has external dimensions of 122 x 69 x 34 mm (4.8 x 2.72 x 1.34″) and weighs 369 g (0.81 lb / 13.02 oz) (including batteries).
Below you can see the front view size comparison of FujiFilm S2800HD and Olympus E-P3. Olympus E-P3 is 5mm shorter and 48mm thinner than FujiFilm S2800HD but it is also 12mm wider. As you can tell, actually this is not a fair size comparison since FujiFilm S2800HD has a built-in lens but Olympus E-P3 doesn't. Once you put a lens on E-P3, its thickness will increase significantly.
Here is the back view size comparison of FujiFilm S2800HD and Olympus E-P3.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Olympus E-P3 is significantly lighter (68g ) than the FujiFilm S2800HD 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 E-P3, the total kit will weigh much higher.
Unfortunately neither FujiFilm FinePix S2800HD (FinePix S2900HD) nor Olympus PEN E-P3 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 Bridge Cameras with Weather Sealing Top Mirrorless Cameras with Weather Sealing
LCD Screen Size and Features
FujiFilm S2800HD and Olympus E-P3'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.