Iran's far from socialist. It has a stance on state intervention and a nationalized oil industry, that's about it. Planned economy doesn't necessarily equal socialism. Anyone can control an economy, what matters is who is controlling it. In Iran it's another form of a ruling class, not the workers.
Quick overview of the History of socialism in Iran. During the waning days of the old Qajar dynasty there was an active socialist movement which merged with the republican movement. This resulted in the short-lived Republic of Gilan which was supported by the young Soviet Union. The Republic of Gilan grew strong, to the point it threatened Tehran itself. The Republic of Gilan was overtaken by the new regime of Reza Pahlavi, an army figure who installed himself on the throne of Iran with blessings from the United Kingdom, under the guise of restoring stability to the country. .
After that the communist movement was driven underground and repressed by Reza Shah. It resurfaced in 1941 after the joint British-Soviet invasion and overthrow of Reza Shah, who was getting too cozy with Hitler and Mussolini. The largest of these communist movements was Tudeh, and its influence increased from there until the overthrow of Prime Minister Mossadeq in 1953. Mossadeq had attempted to nationalize the oil industry in Iran (then mostly controlled by Anglo-Iranian, a predecessor to British Petroleum), resulting in a coup backed by MI6 and the CIA. The resulting crackdowns were targeted at, unsurprisingly, socialist and communist parties, as Mossadeq, though himself not a socialist by any means, was accused of gravitating towards the Soviet Union.
This period in the 1950s was detrimental to Iran's political development. It further polarized politics in two groups, the monarchists and the religious establishment, who at this point were still working together.
There were other workers' organizations, but Tudeh was the largest. I guess another notable grouping was Mansoor Hekmat's parties. The plethora of left groups took advantage of the increasing instability of the 1970s and had a bit of a comeback in power, but their activities was restricted by state suppression, notably by state security forces of SAVAK. When the revolution came, left groups were divided as to how to approach it. Some boycotted right away, others, Tudeh included, tried to work with them at the beginning. We saw the result, but by no means was the Iranian revolution a creation of Tudeh or the other communist parties unfortunately. 1988 saw large scale purges of the left movements.
The other socialist grouping in Iran was among the Kurds. The largest organizations ranged from more general socialist organizations like Komala to social democratic-nationalist type groups like the Kurdistan Democratic Party of Iran. Unlike the rest of the socialist movements these two were mostly growing, though most of it fueled by nationalism.
When the revolution came it was an outpouring of the people's rage against the corruption of the Shah, but most of this fell into religious radicalism. Khomeini's position in the revolution can not be ignored... he was mostly looked upon by the religious community as their leader. One important group that was influential in this was the People's Mujaheddin of Iran (PMOI), claiming to have some "Islamic Socialism", what ever that means. I suppose something similar to Moammar Qaddafi's oddities. At any rate the PMOI burned itself out and lost out to the Ayatollah groupings who had more power among the rural localities. PMOI's influence was more limited to college age people and other youth. PMOI ended up thrown into Iraq where they collaborated with Saddam Hussein, and later onto Europe. Most recently PMOI got taken off the terror listings of Europe and America, probably in return for their help in gathering information on Iran's nuclear program.
In the ensuing years the religious factions fought among themselves (which Iraq picked up on and attempted to capitalize on during the Iraq-Iran War, hoping the Iranians were divided enough). The Kurdish socialist groups were still resisting but liquidated by the regime. To this day though the most active socialist groups within Iran tend to be Kurdish nationalist in nature. Tudeh still hangs around but it's seen better days. The other main ones are various splits involving Mansoor Hekmat's followers.
The others are minuscule and mostly in exile. In the past years Kurdish groups rose up a number of times. Once in 2005 cities in Iranian Kurdistan such as Sanandaj and Mahabad rose up in protest, fairly large ones too, and a number of people were killed. One young student was captured by security forces and dragged around a jeep.
For the next ensuing years there were general strikes in the Kurdish provinces. A recent strike by a joint action between Komala and the KDP-I this past summer (solidarity strike with the five prisoners in Iranian prisons, who were later executed) A repeat of a similar event in 2009.http://picasaweb.google.ca/104752788997 ... 75/zrlHjI#http://picasaweb.google.ca/104752788997092216575/VuEiv#http://picasaweb.google.ca/104752788997 ... 75/UvJvFG#http://picasaweb.google.ca/104752788997 ... 75/CBmEeG#http://picasaweb.google.ca/104752788997 ... 75/GxAoXJ#http://picasaweb.google.ca/104752788997 ... 75/BmkwPD#http://picasaweb.google.ca/104752788997 ... 75/WBdBFH#
This had been happening for awhile but unsurprisingly western media doesn't report on it; Unlike the Green movement, which is mostly approved by the bourgeoisie here.
I'm not very confident of the prospects of Iran to be honest. On one hand there is the reactionary clerics, and on the other hand there is the bourgeoisie "Green" movement. Most of the Iranian ex-pat movements I see tend to be pro-Monarchy as well. The old communist Iranian movements seem to have set themselves up in Canada and Europe, but their influence is negligible.