The whole game really helps you in this aspect, with smooth strategic zooming. As you zoom out, individual units are first indicated by icons, then disappear entirely into their respective planetary systems. When at this high level of zoom, each planet has a trio of display bars that shows the relative number of friendly ships, enemy ships, and structures. Mousing over these bars shows a detailed breakdown by ship type, damage status, and owning team.
There is also the "Empire List," the scrolling outline-style display at the left of the screen. It shows all planets you are aware of, and again an iconic view of the units at that planet. Look at this screenshot:
http://image.com.com/gamespot/images/2006/289/935993_20061017_screen004.jpg
At the top-left, you can quickly see via the Empire List that at the one planet, there are 4 structures owned by the orange team, 3 friendly ships owned by the orange team and no allied ships present (they would show up together with the second orange cluster), and 3 enemy ships, one from the light green team, one from the dark green team, and one from the cyan (sky blue) team. Again, mousing over any of the clusters would show a detailed breakdown.
Also in that screenshot, you can see the plus sign next to the planet icon in the list. If you click that, then the entry will expand like an outline, and show you individual icons for each ship and structure. Mousing over these individual icons will show details on the particular unit, and their current orders in the case of ships. You can see this expanded view a bit in this screenshot from the current beta. The plus/minus signs are now arrowheads that rotate. You can also see the zoomed out strategic view, with the display bars on the left, right, and below the icons for each planetary system:
http://www.bkorion.dk/sins/beta1/nvcplui%202007-05-15%2004-00-49-69.jpg
Icons can also be set to stack, so instead of seeing 8 "scout frigate" icons, you can see one icon with "x8" written next to it. Double-clicking any planet, ship, or star in the list instantly zooms your view to that item.
