In the discussions about Iran’s centrifuge installation patterns, I haven’t seen much mention of Gholamreza Aqazadeh’s announcement that Iran plans to install a new generation of centrifuges at Natanz:

“*New generation of centrifuges which are technologically more advanced than the previous generation will soon be installed* at Natanz nuclear facility,” Aqazadeh told a joint news conference with Russian nuclear agency chief Sergei Kiriyenko at the site of Bushehr nuclear reactor in southern Iran.

It may be that Iran is content to operate its IR-1 centrifuges until it’s ready to install the new generation. Having said that, lots of Iranian officials’ predictions about the nuclear program have had a troubled relationship with reality, so grain of salt and all that.