I too had many ponderings about the possibility of success of Iskandar, and in particular, Nusajaya.
As an interested but unvested property investor at that time, I had considered many various factors. The concept of Iskandar had been discussed for over a decade, and to be frank for many people (especially and even Malaysians who may have heard about it every now and then) the glacial progress was numbing and after a while, had little or no further interest.
Even after its initial concept/development launch in, I believe, around 2006, things were still slow to progress, and certainly the Global Financial Crisis delayed and distracted many individual, corporate and government investors (Medini investors a case in mind).
Slowly over time the relevant Iskandar officials announced the "committed investments" and as it gradually grew larger, one big question still came to my mind, and I presume others' as well. Where were the Singaporeans? How would more investors; personal, business or governments view Iskandar if even the Malaysians could not attract their neighbour to partake and commit into the Iskandar region especially where it is supposedly touted to complement the entertainment, business and personal activities of Singapore? This even despite the massive amounts of money sunk into developing an infrastructure for Iskandar.
Sure, Shangrila (or Traders Hotel), and Gleneagles (Parkway) all had reputable names but had strong Malaysian connection/influences in it. Certain education institutions, Legoland, bits of SiLC etc were I suspect, heavily subsidised and still fell short of showing potential investors the interest of their most important investor - their neighbour. (I specifically did not mention Singapore, but using the word "neighbour". An endorsement by a neighbouring country would send strong signals of intention to the international community, surely?!). The domestic developments could only take the "project" this far, and probably constituted Phase 1 of the Iskandar story.
Obviously we all knew what happened next; billateral relations continued to warm, and the Point of Agreement (railway land etc) signed and sealed. This I think is the political breakthrough, or "political tipping point".
Along the way came with the announcements of indirect Singapore participation. Sunway with part GIC shareholdings, UM Land with part Capitaland, Wellness City to be managed by Capitaland, fresh moves by Raffles Education, MDIS and underlying all these are subtle accumulation of properties by a sheer number of individual Singaporean investors in Iskandar (whom I guess are more nimble in sensing and making investment decisions). This is the phase 2 of the Iskandar development and the development's "tipping point". This phase, borrowing from some media writer's projections, will last till 2015.
I am of the optimistic view that further announcements relating to Singapore's investments in Iskandar would continue to send strong signals and hence endorsement of the Iskandar region. What I am looking for now, is the development of billateral infrastructure - and that must mean the 3rd CIQ in Puteri Harbour (and agreement of the routes, co-immigration / custom facilities), underground tunnel border crossing road, MRT/train extensions, Senai/Changi airroutes and radiowave connectivity (phone roamings, TVs). By then this would signal phase 3 and insofar as property prices are concerned, may look in itself like a fibonnaci wave 3 stock movement itself (and then a wave 5?) - long gradual growth in prices. I suppose this is what we are all after arent' we?
Afterall, with Singapore property prices 30-50 times more, and whilst I don't expect parity in my lifetime, it has a lot of room to grow.