Here is how I see the NA teams performing this split in terms of the Power Rankings:
CLG: Rank 1: CLG shook heads as they made it to the finals of MSI... this is 0-10 Worlds NA we are talking about here... In best of 3 series, CLG must be taken for huge threats with no changes to the roster.
Immortals: Rank 2: 17-1 last split was amazing... only to be struck down by TSM. It was noted that they didn't have enough practice on the patch they played vs TSM. This time around, they will very likely give opponents more respect and not feel so Immortal... yet you do wonder if they might not do as well in a BO3 format.
Cloud 9: Rank 3: Cloud 9 is hard to predict, and part of this is based upon getting Hai back on the roster quickly and regaining form... they could even bring Rush over Meteos... all things to speculate, but the talent is certainly here on this team. The only real question will be how well this team can work as a unit.
Team Solo Mid: Rank 4: This team failed horribly in the Spring Split just to get a playoff buff they always seem to. There are multiple problems this time as well... first off is Yellowstar, the all-star support and shotcaller is gone? So will Bjergsen call the shots and just do everything for this team? Biofrost is still much too untested to trust. Also, the team kept Svenskeren, which in my opinion is a washed up jungler that at this point is really holding this team back when carrying junglers are starting to make a big impact again (as opposed to tanky junglers).
Team Liquid: Rank 5: This team always seems to gets 4th place, once third, and this could be a 5th place. They still got most of their starters. Dardoach's problems could cause the team issues though, and they got some decent new subs for the 10 man roster they like to have... should still be a threat that may take time to ramp up this split.
Team NRG: Rank 6: Quas was a good toplaner, but might be out of practice, Santorin is a true wild card, Kiwikid has probably seen his best days pass. GMB is GMB, and OHQ is kind of unknown (KR players can play a lot worse in NA) that could be another type of GMB. Lots of risk but lots of reward for this roster... but its hard to see them toppling the giants of NA.
Team EnVy: Rank 7: A team with Ninja and Seraph is sure to make many happy. Unfortunately, the rest of the roster looks a bit on the weaker side, but they could find some synergies to make this team not so bad... and honestly, Seraph could be forming into the best top laner in NA... if only he played for a better team though...
Echo Fox: Rank 8: No changes... the team was getting better as last split went on... still this team might need a bit more to compete in NA this split.. possible playoff contender but that's it.
Team Apex: Rank 9: Are you a washed up pro or pro that hasn't played for awhile in LCS, then Apex is the team for you! Unfortunately the competition has only gotten better, which is why other teams didn't want these guys on their roster... but at least they have a 10 man roster and experience in LCS... Cris though... his record in the LCS is quite awful... think Billyboosted and Wickd for comparisons.
Team Pheonix 1: Rank 10: Take a team that was only better than Dignitas last split, add some players that don't look that good, and what do you get? A complete mess of a team that would shock predictors if they finished 8th... anything higher than that is unrealistic for this team... but hey, they outperformed expectations last split (as Impulse).