Those TUAW readers who haven't yet caught Siri fever and purchased an iPhone 4S won't have to wait if they finally decide to buy one. Electronista reports that the device is finally listed as "in stock" at the Apple Store for most countries.
As recent as two weeks ago, availability times were still in the three to five day range, but now the 4S is available immediately in every color and capacity. It appears that Apple has managed to get a good handle on iPhone 4S production, with 37 million devices reported as being shipped in just over three months during the first quarter results call. Part of the improvement is most likely due to the addition of Pegatron as a second manufacturer of the popular smartphones.
With supply finally meeting or slightly exceeding demand, Apple now has to keep a close eye to make sure that inventories of the phone don't start piling up. The company has a reputation for keeping minimal product inventories, so production is probably being tweaked to more precisely match demand for the iPhone 4S.