Yesterday we reported on the numerous battery complaints plaguing the iPhone 3GS. Customers have noted that the 3GS often fails to get through a workday without a charge, and even die-hard Apple fans have had to admit that something is up. Initially we thought that the battery issues were due to the increased functionality of the 3GS, but now the problem appears to be software related.

A new report from Computerworld casts the blame squarely on the iPhone 3.0 update. The report notes that users of other iPhone types began to complain of battery issues shortly after the launch of 3.0. One user noted that, after applying the update, his 3G iPhone started to lose power at a rate of 5-10% an hour. This points to a software glitch or conflict of some sort that is consuming power at a high rate.

One original iPhone owner posted on the official Apple forums that, while his iPhone had once been able to get 5 days on standby off of a full charge, his same phone was now unlikely to last the day. Some 3G owners are reporting incredibly fast drain rates, losing all power within a few hours of standby.

A few users claim to have found some relief by reseting their phones or turning off all extraneous features. Apple recommends turning off all features that are not in use. This is clearly an unacceptable answer to the problem. Those features are what Apple's customers paid for when they bought an iPhone. Apple needs to deal with this problem directly and fix their battery issues before this whole thing gets out of hand.

The 3.1 update is expected to hit soon, and it's possible that this new patch will contain a fix for the battery issue. If so, Apple needs to let their customers know now so they can stop wondering what is wrong with their phones.