First come, first served.

Scalability is a complex problem and it involves at least 3 components: 1) Database 2) Server OS 3) Middle-tier UNIX and Win2K both support scalable databases: Oracle and SQL Server 2000 - you will note that Oracle on UNIX is much (~10x) more expensive than NT and SQL Server UNIX and Win2K are both scalable: some flavors of UNIX support clusters of 64+ processor machines with 64+gb of ram. Win2K supports 16 processor machines with 64gb of ram and the price is much lower per unit of power. The Middle-tier is the key issue to building scalable web systems. This part of the system must support thousands of simultaneously connected (lazy) clients. COM+/MTS, EJB and Tuxedo, and CORBA are the contemporary technologies that provide this support. CORBA is dead alond with Tuxedo and EJB is at least 15x more expensive than a COM+ solution. So in a nutshell, if you need to build a scalable web system, COM+ is currently the only reasonable answer. BTW: To me scalable means that at some point in the future you will be concerned with supporting > 5000 simultaneous users on your site at peak. Lower end systems can be built with any technology you like and you will probably be ok. Let me know if you need more info