There are different ways in SharePoint to access external data (i.e. BCS, custom web service, some might even consider creating a custom service application), but is there a recommended way in SharePoint for accessing external data, or is it on a case-to-case basis? Perhaps BCS would be good in a scenario where external data needs to be presented as a SharePoint list, but if you just need a custom web part to retrieve data from a custom DB table, then building a custom web service would suffice? This question is related to this discussion.
Thanks for your time!