So, how the tables have turned. The last time the sides met, back at the end of October, Munster were the ones flying high and the ones who came out on the right end of a 32-28 try-fest at Thomond Park.
Back then Munster had gone five wins from six games but how things have changed.
Now Munster come to Belfast having now lost five in a row, in all competitions, while it is Ulster who are on the rise as the in-form Irish province.
Ulster boss Les Kiss is being lauded for the way he has galvanised his squad through a wholly victorious December.
Indeed, should Ulster win today and Kiss will have overseen five straight victories for his charges and will start 2016 in the ideal manner ahead of three weekends of pivotal European action.
And, despite their injury profile, Ulster still look better equipped to do the job with Rory Best and Chris Henry back in harness as well as the impressive Kyle McCall at loose-head prop though it will be interesting to see how he goes against former Ulster tight-head BJ Botha.
Though the Tommy O'Donnell and CJ Stander back row combination looks as if it could cause all manner of trouble, Ulster still look the better balanced outfit with Nick Williams giving them go-forward while Franco van der Merwe and Robbie Diack are in especially good form at the lineouts.
Paddy Jackson also happens to be currently Irish rugby's only in-form out-half and his duel with Ian Keatley - sure to be one head-to-head closely observed by Joe Schmidt, the other being Henry's clash with O'Donnell - looks very much a case of advantage to the Ulsterman particularly with Ruan Pienaar in such sparking form as well.
Outside the Ulster half-backs, the midfield combination of Stuart McCloskey - widely tipped for a Six Nations call-up - and Luke Marshall has also been reaping the benefits of the finely-tuned Pienaar/Jackson axis.
And on the wings, Rory Scholes and 200-cap man Andrew Trimble, who might also yet feature in Schmidt's thinking, have been looking sharp.
Also in the side's favour is fortress Kingspan where Ulster haven't lost a PRO12 game since Leinster turned them over in May 2014.
All sounds good, but Munster are a cornered beast and are sure to come out fighting to avoid the likelihood of them becoming more detached from the PRO12's top four.
For Ulster second row Van der Merwe a win today will mean a lot as it will bring him a first victory over Munster at the fourth time of asking.
"It's a bit frustrating," admitted the South African who is currently in talks regarding a possible contract extension.
"But that's not really our focus.
"We don't live in the past and we've got a new focus and we're just using that to concentrate on this game."
"I think they're going to be really up for the challenge.
"That's Munster, they know how to bounce back and we respect that."
While Ulster have made all their four changes up front -Best, Henry, McCall and Lewis Stevenson are in - Anthony Foley has been busy and his starting side sees seven alterations from the disappointing defeat to Leinster.
Botha and Dave Kilcoyne are the starting props while Mark Chisholm - a familiar foe for Van der Merwe from their Super Rugby days - is at lock and O'Donnell ready to cause mayhem at openside flanker.
In the backline, Keatley returns from his notable difficulties in Europe while Lucas Gonzalez Amorosino and Ronan O'Mahony are on the wings.
We can't necessarily expect a high scorer like last time these two sides met in Belfast
That time Jackson's late conversion levelled the affair at 23-23. It might just end up being another weather-beaten arm-wrestle, but the contest should still have plenty of edge and drama to it.
Oh, and a likely Ulster victory.