i have been residing in canada for 38+ years most of it in toronto.
here is my experience.
initially when the community was getting foothold here, there was more of 'indian'ism. we even had an indian credit union (co-operative community bank) but within 10 years that folded. very soon, people with the comfort of numbers, started gravitating to micro groups, same language, caste
again the old fogies of the 70s and 80s like us, do not mix with the new young crowd, fresh off the boat from india or dubai. our children, who are the same age, for cultural incompatibility do not mix with the newly arriveds.
the second generation, do not know the difference, or appreciate the difference between gujju, punjabi or madrasi. since punjabi is the overwhelming culture by virture of numbers, everyone gravitates towards punjabi culture. not many tambram kids are aware of our unique rituals, to carry it on to the next generation, and neither do the parents care. atleast 75% if not more, though i am not sure, if the parents would agree to this.
initially there was one south indian temple, a unified effort of overwhelmingly iyers with representation from iyengars, telugus and sri lankan tamils. then in the 1980s these overwhelmed everyone not only by their numbers (est 4 lakhs in toronto) but also by their devotion. the ganesha temple is a thriving example of devotion carried across the seas by sl tamils. the management is nominally tambram, but the tradition and devotion is sri lankan. the odd bajana group congregates there during weekends, but festival celebrams are 99.9% sl tamil.
in addition to that enterprising tambram priests (indian or sri lankan) have started 'private' temples which are also flourishing.
north indians, west indians, gujjus have their own temples, not that others are not welcome or forbidden go there. but it is not usually done. everyone likes the smell of their own kind. that is the way it is.
the iskon temple is a convertd protestant church, so clean that you can eat off the floor. except you get hounded by the white converts, so that you cannot wait to get out.
the new temple is shringeri mutt, which is becoming a sole tambram strong hold (whispers here is to keep the sri lankans out) showing that our generation and the newly feeds from india are strong in their avoidance to any other group than tambrams even when it comes to religion. there are also several private vathiars, doing good business, and flying all over canada, to remote areas, for weddings, poonals or shraddhams.
the kerala christians keep to themselves. the public must understand that the white culture is irreligious, and the indian catholic has not much in common with a white protestant or filipino catholic other than religion. culturally they do not mix.
same goes with the indianmuslims. most mingle with pakistani muslims, because they all belong to the same cultural roots of north india, and not because of any anti india feeling. same goes with bangladeshis who do not move with pakistani or indian muslims, or with banga hindus either.
ismailis, a muslim sect under agha khan, are not considered 'muslims' by pak or indian muslims. their women are liberated and the community is into education and are reaching great heights in management and education. they keep to themselves too.
so, we are all little islands, a mosaic in canada, each with our identities and brag lines.
the one occassion when there was a pan india celebration was during the 50th anniversary of indian independence. there was a cultural program of all of india, ie dances from all parts, and that was it.
without the urgency of a war, poverty, natural calamity, there has been no need for strong virulent identity assertation, unlike sri lankan tamils, who have been and still traumatized by the fate of their brethren back home. prosperity, i am afraid, does not provide a clarion call for unity or sacrifice or charity. this is the reality.
it is nice to believe that once out of the homeland, we indians congregate together. not true i think.
maybe it is our familiarity with english, or the familiarity of places due to the internet or hollywood movies, we may not feel as strange to foreign lands these days, like our grand fathers did.
after all, perhaps, yaathum oorey, yaavirum keLir, is now becoming more of a reality
thank you.
ps the only group that stick together like fevicol, are mainland or HK chinese, but then i may be prejudiced here.
a price too high that i paid,though i comfort myself saying zindagi ek safar hai suhanna yahaan kal kya ho kisne jaana 
