For me personally, GooogleMapsAPI wins this contest by a huge margin. The biggest win for Google's take at GIS is that it uses GPS coordinates -- specifically, you normally find the hash with { ih, kb, ...} keys ... I do not actually remember the keys but they are there and they actually represent the ... what was it? .... longitude and latitude of a coordinate. My knowledge of the meaning underlying the coordinates themselves is lame. I know it. I do not apologies for it. Simply because for me the physical meaning is not important, as long as I can plot them on a 2D or 3D visualization. In fact, I once plotted a worldwide AS-level network topology randomly assigning X and Y only to realize that the world was on its side. You could actually tell because the ISPs formed pretty god outlines of continents.
Now, all I need to know about GISes is the datatypes. By far the most popular datatype in traditional GIS is SHAPE (.shp). Sometimes these files are referred to as SHAPEFILES. You can read all about the format here, but I would recommend to see the diagram from here:
Sorry for the Japanese, but I could not find English diagram with the same level of visual clarity. The wikipedia page definitely does not tell you that right away. The .SHP format is very simple:
(1) It is a vector format.
(2) It can be in 2D-mesh or 3D-mesh forms, where the 2D and 3D do not stand for coordinate dimensions (which is why Google search on the format will only confuse you), but rather precision of the coordinate itself (see figure above). Simply put, 2D-mesh gives you 10x10km dots and 3D-mesh gives you 1x1km dots.
I once officially requested Tokyo road map from some official association, got their CD ... only to find out that the data was in 2D-mesh format. This meant that the center of Tokyo on the plot looked like a single dot. Literally!
That was the point at which I decided to just use Google Maps as my main GIS system. YES, this improved precision of my datasets, but NO, it did not solve all my problems -- the big problem further on.
I recently had to use Google Maps as GIS to build road maps (graph structures) collecting certain places. The problem I stumbled upon is collaboration. Specifically, collaboration in building datasets -- not using them. Majority of GIS portals I know (included Google Maps Engine) are there for 2 purposes:
(1) to use a GIS dataset together
(2) to build a dataset based on the interface provided by the portal.
The simple purpose I am trying to pursue is left unfulfilled by both the above. Which is actually strange because quotas on requests exist for any existing API -- GoogleMapsAPI or ArcGIS, although it could be in slightly varied forms -- ArcGIS is paid from the start and has rather big quotas while GoogleMapsAPI has very restrictive quotas in its free form.
Why quotas? This is simple. Google as well as all other big players have to ration access to their Big Data. Imagine all free users having unlimited quotas to all Google APIs?! Specifically, a free GoogleMapsAPI client (per IP) has the daily quota of 2500 requests. This is key because ... say, if I have 300 locations and I need to build an undirectional (A-B = B-A) graph among them, I need to make > 35K API requests. About a month for one client. About a day for 30 clients. About an hour if the crowd piles up and helps me with it ... on demand. The simple idea behind online collaboration on this topic is that I would borrow daily quotas from users who ... in their majority ... do not use much of their daily quotas anyway. Note that Google's Terms of Use do not prohibit such a use of its API.
For example:
http://t.co/3SmOedz2l0
is a simple serverless web application which uses client's daily quota to suck routes from GoogleMapsAPI and store them in my Dropbox folder. All clients write to the same folder. Collisions are resolved by the web application. This is a very simple collaboration.
Note that its purpose is different from that of default modes of ArcGIS or GoogleMaps (API or Engine) and cannot be created by the either of them. I am surprised to find myself in the position that public collaboration on a (useful?) dataset is completely impossible just because it departs -- a little bit -- from the default use.
Let me go one step deeper into this rant. I tried posting a request on Twitter with useful hashtags like #googlemaps #googlemapsapi #datasets, etc. in three languages, only to find out later that my message did not show up in none of the hashtag streams. I do not know what the criteria are used by Twitter when it aggregates its hashtag streams, but it looks like posts saying "I really like Google Maps" are more worthy the inclusion into the stream than a meaningful post. In the end, my posts ended up viewed only by the few (3?) people I have as my direct followers. Not a very social person, obviously.
Now I am posting it here. Let's see if I can actually find a way to broadcast this message beyond the small social box in which I live.
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