Gorby was an unreconstructed (neperestroen) communist, his plan (actually his mentor Andropov's plan) was to try and breath some life back into a decaying Soviet Union. Despite all the CIA projections of Soviet military and industrial might, the Central Committee members knew they were circling the drain. Reagan and Thatcher embraced perestroyka only so far as it would let the Pandora of freedom out of her box.
Sort of like both Bushes' approach to China.
Boris Yeltsin was an opportunist who, like Putin, was in several right places at the right times. He was the governor/mayor of the Sverdlovsk (now Yekaterinburg) district and ordered the excavation and release of the Romanov family's remains. This got him noticed, slid him into the "President of Russia" position, a ceremonial post in the Soviet Union. Gorby fell during the hard-line commie putsch - soft-line Gorby hurt some feelings with "Glasnost" (open critique of corrupt officials) and by pulling out of Afganistan.
Yeltsin seized this opportunity, jumped on a tank with an uncommitted army unit and declared the Soviet Union dead. The other army units would not fire on their brethren, and by default only Russia remained.
Yeltsin stood for election, and through Chicago-style chicanery was elected and re-elected. I could spend megabytes of space describing the Byzantine relationships between his family members and the oligarchs, but suffice to say Moscow looked a lot like Cook County Illinois is those days. Everything in Russia that could be stolen, was. A billion US dollars left Sheremetevo for Geneva every day. When Duma deputies tried their own putsch, Yeltsin's tanks opened fire and burned the parliament.
But Yeltsin filled an important position - he gave a very sick Russia some bedrest, gave the people a chance to get used to some ideas besides Marks-Engels-Lenin, and the first taste of social and economic freedom in their entire history.
Putin is a cipher. He is aesthetic, with a taste for martial arts, Vysotskiy, and eschews alcohol. He may seems less corrupt, but his history in pre-Yakovlev Petersburg reads otherwise.
As president, Putin went after a few oligarchs and reopened the Chechnyan question that Yeltsin swept under the rug, but IMO he is not firmly intrenched. I see that he still bows now and then to Russia's traditional troyka of king-makers: the nobility (aka communist party, oligarchs, monopolists, gangsters, etc), the general staff, & the secret police. Russia acts as if she had a monolithic nation and foreign policy, but foreign policy is but a game for a politician to play to enhance his domestic standing. Whatever policy keeps the daggers in their sheaths is what a Russian leader uses. If LUKoil stands to lose tons of money in Iraq, or army egos are suffering because Russia is selling out its formerly very close friends in Iraq, Putin will toss them a bone. Probably one that American tax-payers bought.
Putin's reign will probably be as long as Yeltsin's, but the politics will be more like NYC than Chicago. FWIW.