Citigroup lost (actually, sold) its red umbrella sometime in 2007 and adopted the red arc which now reads as a red (dangerous) small bridge. AIG has no little corporate abstraction, it stands with its initials. If pronounced as a word -- "aig" - well, it rhymes with gag and brings to mind a kind of choking yelling noise. Bank of America has an American flag as landscape, farmer fields on a distinctive curve as it viewed from above, perhaps a corporate jet. RBS has a geometric tesselation that would make a fine wallpaper - arrows pointing inward to a blank circle...the emptyness of the inside does not read well these days either.
Redesign ideas? An abstract metamorphosis of these logos will no doubt be coming soon. Colourwise, Missmc recommends out with the red and in with the green. What else? American references need to be avoided for a while. Fonts? They must get serious. Times-Roman or something nostalgic. Perhaps most importantly, all these institutions need to be renamed before they are re-logo'd. I can see you all smirking with venomous ideas. Stop that!