Using pre-rendered Map Tiles for maps is not really new but it hit the big time when Google Maps was released and changed online mapping forever. Base data that doesn’t change often can now be displayed very quickly while ever changing data could be displayed as overlay markers. We’ve heard from many of our users that what they really want is the ability to quickly publish maps (2D and 3D) online without a lot of hassle. Google Earth provides a good way to do this because of its ease of use and massive installation base. However, sometimes they just want 2D maps (for aesthetic or licensing issues) that portray their data and get it into their users hands as quickly as possible. So what's needed is a way to publish your map tiles on top of mapping clients. This can be done with several of the mapping APIs including Google Maps, MS Virtual Earth, OpenLayers and the soon to be released ArcGIS Server (albeit at some pretty steep prices). Creation of the tiles is left up to you with the help of some tutorials and in the case of MS, the great MapCruncher software. However, these processes use a single image that is subdivided and in the case of 3D clients, resampled to create low resolution versions. A better way is to cut tiles directly out of ArcMap, where the size of the extent is unlimited and the changes in levels produces both excellent resolution and scale depended rendering (e.g. when you zoom in or out, layers can change visibility and symbology). So, to get the best possible set of tiles, you really need to work directly inside ArcMap as opposed to exporting images and then cutting them up. (Note – the tile cutter geoprocessing tool used for ArcGIS Server uses the optimized route, which is good) 2D Clients
The goal of the Arc2Earth publisher is to create tiles and marker overlays easily and publish them to a web server (or Amazon S3) as static files. This avoids server software completely. It won’t avoid it for large organizations or people who have extremely dynamic data that cannot be batched, but it does help for the vast majority of users. Once the data is created, all the necessary scripts and metadata are created and published along with it. The browser clients created are Google Maps, Virtual Earth and OpenLayers which become immediately available for viewing one the publishing is complete. Below are sample Google and VE maps after publishing a small area of a tax parcel map. The user can opt to export the current map extent or the full extent of a map. (note - this functionality is in the next release of Arc2Earth so it is not available for Trial right now) 
3D Clients
Although it’s not quite working yet, one of the goals is to automate how the map tiles show up in the 3D clients as well. In the case of Google Earth, KML region data will be written and published along with the tiles. As for VE3D, the map tiles should work right out of the box but unfortunately the critical GetTilePath method currently does not work in the 3D API. I suspect they’ll get something working in the future so your tiles will eventually just show up automatically. It could work now if A2E used their built-in tile naming convention, however I think it’s more important to support the OSGEO spec for naming in the long run. I’ll have some more on this in the future.
Marker Symbols
Its great to have map tiles of your own data but many times you’ll want to click on features to drill down into them. In the wizard, you can specify what point layers you want to have rendered as overlay markers. The regular Arc2Earth InfoWindows settings will govern what is displayed on the popup windows in either GMaps or VE. All of the data and the javascript to integrate it into the web pages will get automatically created and stored with the tiles. no fuss, no muss.
Amazon S3 Web Storage
This could be one of the coolest web services out there today. Basically, S3 is a huge online storage engine that gives you unlimited capacity based on very reasonable prices for bandwidth and storage. What’s even better is the scalability you’ll get when using their backend, scalability that would cost you huge amounts of money to do yourself. So, while the default option is to create all of your map tiles and metadata in a local folder, this is a great option for getting your data on the internet without having to worry about servers (or server software for that matter). Arc2Earth takes care of setting up your online “buckets” and will then do all communications with S3 automatically in the background. It’s just a really easy way to get your data online quickly, why have to worry about servers at all?
Better Drawing Quality
ArcMap has tons of cartographic options when determining how you want your maps to appear. When printed, the end result is usually spectacular. However, the onscreen representation can sometimes look a little rough and doesn’t really represent what will be displayed on the printed version. The vast majority of people use ArcMap to produce printed maps so this is a good thing although I would have liked them to improve the screen versions of symbols in the shorter term. Long term, the 10.0+ versions should handle this but that doesn’t really help us now and since we are using ArcMap to create the map tiles, some improvements are needed. 
A first attempt at helping with this problem is to swap out symbols during the export process so that the drawing commands use .Net equivalents with the anti-aliasing support turned on. It’s a tricky issue but with the next version of A2E, we’ll support simple, cartographic and multi-layered lines. If this option proves to be successful (and actually wanted by the community), we’ll add more support for the more esoteric symbols. Personally, I think the map output looks much better and is more in line with what people expect from online map tiles. If you don’t like the output and just want the standard ArcMap rendering, simply unckeck the option in the wizard. YMMV. Below are sample outputs comparing the standard rendering versus the Arc2Earth rendering. 
so, the next big release of Arc2Earth will have tons of new features. We’re going to have a beta version next month so if any existing users would like to test this functionality, please contact me above. Also, we’re attending 2 GIS conferences next month, so if you see the Spatial Data Logic booth, feel free to stop by and say hi. We’ll be at the ESRI MUG in Philadelphia (November 27) and ESRI Boston Solution Expo (December 5th) Listening To: The Strokes - Under Control - Room On Fire
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