Some teams will make a jump in the polls after a tough loss to a highly ranked opponent, but Iowa had 2 major things working against them:
1) Not a "name" program; people want to see blue bloods ranked, and the pollsters will go out of their way to make sure they are there (See Fla St)
2) That was a very lopsided game statistically. If Iowa had gone toe-to-toe and came up one play short, they might have gotten more consideration.
The truth is that pollsters don't know what to think of the Hawks right now. Looked quite mediocre first 3 weeks, then despite being dominated statistically, were in position to put away a highly ranked team. This game could make a difference later on, though. If Iowa loses 4+ games, then this game will be written off as a fluke. If they beat Wisky or OSU and/or win the division, then this game will hold water as a "quality loss."