You'll probably need a few sentences to go over the parry and strength quirks because there's base gear, trinkets, enchants, and gems to cover.
On the base gear front it'll be fairly obvious that parry goes up considerably since all warrior plate has strength on it. What needs more thought are the situations where we have lowered strength on a piece to increase a secondary stat. Thanks to reforging the extra secondary stats will probably be more useful than the raw strength lost.
With trinkets it's worthwhile to note that there are no parry trinkets in heroics or raids in MoP yet, so if tanks want avoidance from trinkets it'll have to be with dodge or strength. It is possible strength will come out ahead because it's almost as effective as parry but also provides some extra oomph to SBar, even though that extra contribution isn't much compared to what vengeance contributes.
With enchants there will be choices like
Bracer: Major Dodge versus
Bracer; Exceptional Strength. 170 dodge versus 170 strength might end up favoring the strength enchant for the same reasons it does for trinkets: Still worth about the same as parry, but helps with SBar (and DPS).
Both trinkets and enchants can do double time for DPS pieces too. Base items can also do it, but with the overlap only being expertise/hit/mastery and the possibility of a DPS spec not liking mastery it's less likely to be fully effective.
Gems change things. If it were 1:1 strength, parry, and dodge, strength might end up winning. Because secondary stats get double the rating amount though, the secondary stats are the clear winner for absolute ratings. Since expertise, mastery, and hit cover red, yellow, and blue sockets, respectively, worrying about strength probably isn't an issue.
Speaking of gems, there are the meta gems to consider.
[Austere Primal Diamond],
[Eternal Primal Diamond], and
[Effulgent Primal Diamond] all have their uses. I have not seen any discussion on them yet but chances are
[Austere Primal Diamond] will minimize relative damage taken more than
[Eternal Primal Diamond] on physical fights as per the
numbers on page 1. For absolute damage reduction there will probably be a certain mastery point where
[Eternal Primal Diamond] overtakes
[Austere Primal Diamond] if it doesn't already do it from the start, but the various fights really need to be weighed to consider how much damage is blockable.