Shannon, the eight-time champions, lead the way in Division One, with Munster's Marcus Horan and Anthony Foley having made notable appearances for the Limerick giants as replacements, while last season's beaten finalists Cork Constitution sit just two points behind them.
The surprise packets of the league so far have been Cork side Dolphin who retained third place with an impressive 21-5 dismissal of Lansdowne last week.
David O'Mahony's charges, helped by talismanic Munster player James Coughlan and former Con out-half Barry Keeshan, have done well so far but with four of their five opening games in the league having been at home, Dolphin will have to take that form away from Musgrave Park to stay in the play-off picture.
UL Bohemians and Ballymena are both pressing for inclusion in the top four, but defending champions Garryowen have so far failed to hit the heights of last term and they currently lie in seventh after defeats to Shannon and Clontarf.
However, only four points separate fourth-placed Bohs and UCD in ninth position so with two rounds of games to come before the Christmas break, the table could have a completely different outlook come December 15.
In the lower reaches of the table, St. Mary's College, who only chalked up their first win last weekend, and Dungannon have both struggled to get out of the starting blocks and the pair sit in 13th and 15th respectively.
Old Belvedere and Greystones, the two clubs promoted from Division Two last season, have two wins between them and look to have a fight on their hands to stay in the top tier, although Belvedere have shown some spark by picking up three losing bonus points and 'Stones have been unlucky with injuries.
Three Munster clubs sit on top of the pile in Division Two currently, with unbeaten duo Young Munster and UCC sharing the lead and Highfield filling third place on scoring difference.
Munsters, who lost in the semi-finals last season, are certainly heading in the right direction again this term under new coach Mike Lynch. Their 38-3 success at Clonakilty and a 36-0 victory at home to Suttonians have been the pick of their recent wins.
Another new coach making waves is UCC's Conor Twomey whose bunch of young talents, including recent underage internationals Scott Deasy, Ian Nagle and Neilus Keogh, have already matured into quite a team.
The Cork students set their stall out with two battling wins at Ballynahinch and Belfast Harlequins and are one of only four teams left in the AIB League with 100% records.
Things are particularly tight behind Munsters and UCC with only three points separating Highfield in third and tenth-placed Barnhall. Former top flight duo Harlequins and Buccaneers could soon make a surge for the play-offs as both lie in seventh and ninth respectively.
Malone are also sitting nicely in fourth at the moment in what is their 15th consecutive season in the second tier. Coach Andy Dougan has got his side playing some high quality rugby, as evidenced by their three wins on the trot over Bective Rangers, Suttonians and Thomond.
Bective could do with a slice of luck - coached this season by former Irish internationals Stephen McIvor and Gabriel Fulcher, three of the Dublin 4 outfit's four defeats have been by seven points or less.
Down at the bottom, Clonakilty and Suttonians, who contested the 2005/06 Division Three final at Lansdowne Road, are both still chasing their first win since the league kicked off in October.
The trail-blazers in Division Three so far have been Bruff. The Limerick side missed out on promotion last season although they did gain some consolation by beating Wanderers in the play-off final.
Eugene Murnane's men are in flying form having posted five wins in their five league outings to date. Not only are they top of the Division Three standings, but the Cathal O'Regan-captained side also boast the best attack (136 points) and the best defence (17 points) in the entire AIB League.
That is some going - they are conceding an average of just over 3 points per game. Indeed, Bruff kept both Nenagh Ormond and Waterpark to 'nil' in their last two outings.
Second-placed Instonians showed their battling qualities by edging out both Queen's University and Naas recently and Clem Boyd's side, with former Irish international Niall Malone having an influence both on and off the pitch, will hop to stay on track and better last season's run through the semi-finals.
There is a big Ulster representation in the top six with Inst being joined by Queen's, Banbridge and the Willie Anderson-coached Rainey Old Boys.
Despite some sterling individual performances, City of Derry are currently residing in 16th place, one place worse off than last season. Former club captain Neil Stewart is in charge this season and while results have not gone Derry's way to date - particularly last week away to Rainey - they do still have time on their side.
In mid-table, Nenagh Ormond and Sunday's Well both have the foundation of three wins from five games to build on, while 13th-placed County Carlow, with Australian Jason Jones in the coaching hot seat, dug deep to beat Banbridge 3-0 last Sunday for their first win of the league campaign.
Despite two recent defeats, Naas, who came up from the junior ranks last term, have made their mark on the division with wins over City of Derry and County Carlow. Coached by Andrew Melville, the Kildare men have two tricky away trips up next against Corinthians and Sunday's Well.