If you're still trying to get your head around how all the search technologies co-exist and (dare we hope) integrate together, see Arpan's "Enterprise Search 101" posting.
Hidden away down at thebottom of it as well, are a useful couple of paragraphs on licensing which describe how the different SKUs are going to operate. We're expecting a formal announcement of the licensing model mid-August, but this may help in the interim.
"It's important to note that there are different SKUs available that contain SharePoint search. Depending on your business needs, you want to explore the following.
1. SharePoint Server for Search. This is a "Search SKU" and the licensing model is dollars/server. It comes in two versions (Standard and Enterprise) and depending on the number of documents, you want to choose the appropriate one. This SKU builds on top of Windows SharePoint Services (WSS) v3 and has all the extensibility that SPS 2003 has today. There's also an upgrade path from the search SKU to the Standard and Enterprise versions of SharePoint Server.
2. SharePoint Server w/ Standard CAL. This is a Server/CAL licensing model and provides a lot more functionality across the board than the "search SKU". This is also built on WSS v3 and gives you portal and enterprise content management features (for specifics on what SharePoint Server provides, read this post). From a search perspective, this adds the ability to search people and introduces a new extensibility and UI experience known as the Search Center. People search can be enhanced with Knowledge Network for SharePoint which is an add-on if you own this SKU.
3. SharePoint Server w/ Enterprise CAL. This is a Server/CAL liecnsing model and in addition to the capabilities provided w/ Standard, this provides rich Business Intelligence and Forms capabilities. From a search perspective, above and beyond what Standard provides, this introduces a new feature known as the Business Data Catalog (BDC) that allows you to easily search structured LOB systems without writing code. Out of the box, we plan to provide integration with SAP and Seibel as well as any database via ADO.NET. Any LOB system that exposes information via XML Web Services can be connected to.
Please note: While #2 and #3 provide search functionality, they provide rich Information management features that helps information workers share, collaborate, find and retain information end-to-end. It's more than search!
In recap (all will be available in the Office 2007 timeframe):
1. Office SharePoint Server for Search follows a per server licensing model, is extensibile, crawls file shares, sharepoint sites, web sites, exchange pfs, lotus notes databases out of the box. it comes in to versions: standard and enterprise – you choose depending on how many docs. it upgrades to the other office sharepoint server skus.
2. Office SharePoint Server Standard follows a CAL/server licensing model. It provides much richer features than the search SKU. From a search perspective, it provides people search and the Search Center.
3. Office SharePoint Server Enterprise follows a CAL/server licensing mode. It provides more features than Standard such as BI and Forms. From a search perspective, it introduces the Business Data Catalog (BDC) that allows you to connect to LOB systems without writing code."
unclaimed blog