No, they are not going to announce they have built a bomb. That's daffy. If they were that stupid, they would get hit by Israel and the US today instead of 3 or 4 months from now. Any such announcement would unite NATO and the US against them - and even cause Russia and China to back off their support.

Much more likely, they will announce their success in mastering the entire nuclear fuel cycle, including the complex process of building their own nuclear fuel rods. Previous announcements have hinted that they were close to developing their own capabilities, so it is very possible they have been able to accomplish this feat.

This is bad enough, since Russia was supplying the rods for the Bushehr nuclear plant and the spent rods were sent back to Russia to prevent the Iranians from using them to make plutonium. If they can make the rods themselves, no telling what they will do with the spent fuel.

Haaretz:

In the coming days the world will witness Iran's announcement of its very important and very major nuclear achievements," Ahmadinejad told a crowd at Tehran's Azadi Square in a speech broadcast live on state television. He gave no details.

"The world should know that despite all pressures, Iran will not withdraw one inch from its principles and [nuclear] rights," he said.

"All countries have put pressure on us for not obtaining nuclear know-how, but all these pressures were futile. We not only now have the nuclear know-how but also are capable of providing for our [nuclear] needs by our own local experts."

In recent weeks, the United States and its European allies have imposed new sanctions to try to force Iran back to talks. Iran says its nuclear program has only peaceful purposes.

The United States and Israel have not ruled out military action to prevent Iran from obtaining nuclear weapons. Tehran has warned of a "painful" answer, saying it would hit Israel and U.S. bases in the Gulf as well as block the vital oil shipping route through the Strait of Hormuz.

I should add that the conversion process to plutonium is long, laborious, and almost certainly beyond Iran's capabilities - today. Two or three years from now might be a different story.

Mastering the fuel cycle is just one more indication of Iran's increasing technological expertise in managing their nuclear industry. Bombing may destroy the physical infrastructure of their program, but it can't wipe clean the knowledge the Iranians have gained.

The nuclear genie is out of the bottle and there's no way to stuff him back in.