The first round of an Olympiad, as is generally the case with any Swiss System event, is typically full of mismatches. The big three (Russia, the U.S., and China) all flattened their opponents with 4-0 shutouts, and so did the Azeris, the Ukranians, the Poles, the French, and the Indians (for starters). Some individuals on some strong teams were nicked for draws - Zoltan Almasi of Hungary, Jon Ludwig Hammer of Norway, Georg Meier of Germany, and Ivan Salgado of Spain were among those giving up half points against considerably lower-rated opponents. Overall though, the favorites performed as expected given the mismatches.
One big exception: the Bulgarian team. The team is lacking Ivan Cheparinov and Kiril Georgiev and isn't as strong as it could be, but Veselin Topalov is playing and their team rating of 2596 still ought to be enough to dispense with the Sudan (average rating 2174). Topalov did his job on board 1, defeating 2199-rated Samir Nadir with White in 31 moves. No problem. Bulgaria's other White game was also a success, as GM Krasimir Rusev (2548) won easily against Asim Ali Elobeid (2109).
Unfortunately for the Bulgarians, they didn't have any more success than the Sudanese when it came to playing Black. FM Abubaker Tagelsir (2216) simply crushed GM Momchil Nikolov (2585) on board 2, and Abdelazeez Mohamed Abdalla (2183) convincingly outplayed IM Martin Petrov (2458) on board 4. Very impressive.
On the women's side it's really a big four, and they - China, Ukraine, Russian, and Georgia - all got through with 4-0 scores, as did other favorites like the Azeris, the Indians, and the Americans.
Look for plenty of blowouts in the round 2 action as well - it takes a little while before the big teams start to meet in this 11-round event.