<p>I am working on a project that I need to use the Infragistics WebGrid control for some lists of data. I am loading the data on the client-side using JavaScript for display on a Map, and then I need to display that same data within multiple WebGrids. All the data available will be displayed in the WebGrids, but only a subset of the data (only that which is currently within view) will be plotted on the Map at any given time. Since I am loading the data using JavaScript/Ajax, I would like to only load it once, and use the same mechanism to populate the WebGrid control with data too.</p>

<p>Does anyone have any tips/pointers on working with the WebGrid completely from within client-side JavaScript/Ajax code?</p>

The only thought that comes to mind is performance-related. We found that dynamically creating and populating rows for an UltraWebGrid was appreciably slower than we would have liked.  (In our case we were moving rows from one grid to another and hit performance issues when the number of rows was too great.)
If I was doing something like you describe today, I would populate the grid from the server side if at all possible, and the display the relevant values on the Map from there.
As an added disclaimer, we used Infragistics 2007.1; I do not know if 2008.x is better in this area.