"Embryonic democracy" is one of those phrases people use without necessarily thinking it through. Essentially it means "not a democracy" but with the idea that it will be. Perhaps it rests on the progress myth that things inevitably get better and that democracy is part of the natural progression of history. Democracy is something that needs to be nurtured and defended and reinvigorated.
"Embryonic democracy" seems to be used alot when a country pays attention to the form of democracy but not necessarily to the substance. The country has a free election (or at least what diplomats call "generally free and fair") but the institutions of democracy are weak. Iraq is an "embryonic democracy" too, as is Ukraine, but lumping Iraq and Ukraine and Yemen together in one category like "embryonic democracy" requires ignoring lots of fundamental differences. Turkey and Pakistan have been embryonic democracies for decades, which basically means they have some democratic institutions and some undemocratic ones, and occasionally power shifts from one to the other. Germany was an embryonic democracy until 1933. Even under the Empire there was competitive politics, rising capitalism giving more people a vested interest what the state did with their wealth, and social debates; and many of its subordinate states like Bavaria were even more liberal (in the 19th century sense). But that embryonic democracy died rather quickly after the Nazis achieved power.
Yemen does have one advantage, though, which is that no one really cares about Yemen. From the 1960s to the 1980s, the Yemens were caught up in regional and global rivalries. The Soviets supported anti-British Communist insurgents in what became South Yemen, and then the Communist regime there after the British left. The USSR got access to naval facilities on the island of Socotra, and hoped to create a network of client states that would give it control over the southern entrance to the Red Sea. Somalia's socialist regime was a Soviet client too, but when Ethiopia's Communists took power, the Soviets found an even more ideologically pure ally. Initially, through Cuba, the Soviets tried to bring together all three - South Yemen, Somalia and Ethiopia - but Somalia balked and instead invaded Ethiopia. The Soviets and Cubans sided with Ethiopia, and Somalia decided to become the US' new bestest buddy. Then Communism collapsed in the USSR, the Cold War ended and no one cared about their client states anymore.
In North Yemen, regional rivalries played a bigger role than superpower ones. In the 1960s the big rivalry was between the Arab socialists - primarily Nasser's Egypt, Ba'athist Iraq and Syria, and Algeria - and the conservative pro-Western monarchies - Jordan, Morocco, Saudi Arabia, the Gulf States and non-Arab Iran. This had a superpower proxy component too, of course, as the socialist regimes all became Soviet clients of varying loyalty. After the Zaydi monarchy was overthrown, the Egyptians tried to use North Yemen as a weapon against Saudi Arabia. Their role in the civil war there was particularly brutal, involving the use of chemical weapons against royalist forces. But by the 1970s Nasser was gone and oil wealth gave the Gulf monarchies a lot of power to buy off the Egyptians, Syrians and Iraqis. And they could paper over their own differences by jointly hating Israel.
When North and South Yemen unified it took me by surprise. Apparently their ostensible ideological differences amounted to nothing. But it was hardly a triumph of democracy. The Yemen Socialist Party continued to control most of what had been the People's Democratic Republic of Yemen and the republicans continued to control much of what had been the Yemen Arab Republic, with smaller royalist, Islamist and other parties. Power remained heavily tribally-based, so the parties remained regional parties. These various interest groups are heavily competitive, which leads to vigorous politics, but insofar as the people at the bottom still have little or no say, even competitive elections among these groups isn't really democracy.
Yemen's most recent Freedom House survey is
here, although their "Freedom in the World 2005" survey ought to be coming out within the next few weeks.