There have been lots of rumors lately of release of iphone 5. May be this is a rumor but iphone might release its new version in Early 2012. There have been lots of competition with iphone in smartphone market because Samsung and sony Ericson had been increasing its market in Smart Phones. There used to be a dominating days for iphones but these days Samsung mobiles like S2 have been giving a lots of competition to iphone so Iphone might update its mobiles in this 2012.
Its latest release of iphone 4 has increased its reputation in smart phone market but it has got lots of competitions within the market so may be iphone will update its 2012 version soon. Lets wait for this.
I do not think that there is any official announcement of iphone 5 yet but this might just be a rumor.