While spluttering champions City have a tricky assignment at Newcastle, United host lowly Sunderland on the back of four successive league victories and with confidence sky-high following Robin van Persie's stoppage-time winner at Eastlands.
Giggs has seen 12 previous title-winning teams take shape during his career at United and the veteran Welsh midfielder is beginning to sense another dominant team forming at Old Trafford.
Asked if the win over City would provide a major boost, Giggs said:
"It should do, purely because of the way we performed. We have got everything in place for the busy Christmas period and the confidence of such a great result.".
"We accept that we are letting too many goals in and we've had to come from behind too often, but the signs are there that this could be a very good season for us.
"The wins against Chelsea, Newcastle and City away have been our three best performances and you probably can't get three bigger challenges."
While Giggs and his United team-mates can contemplate a successful second half of the season, City are facing a fight to salvage their campaign.
Roberto Mancini's side have already crashed out of the Champions League and another setback at Newcastle this weekend would deal a hammer blow to their hopes of retaining the title.