Starting a new position in a couple of weeks as a developer using Netweaver, never even seen the program, it's going to be fun!

Netweaver is SAP's name for a slew of software components all making up their "middleware" offereings. The root of the technology is there WAS (web application server) technology which allows you to develop in java. This is a relatively new technology to SAP and isn't as mature as other JVM's like IBM's Webshphere. There is also an EAI (old term) technology component they call their XI server. This works much like IBM's data messaging middleware. Has connectors for different technologies and either does sync or async data shuffling back and forth based on business rules. There is also portal technology that goes under the netweaver umbrella. Netweaver is all inhouse developed software from SAP and has been around for only a few years. If you are used to working in some of the more mature java platforms then this should be an easy transition as it won't be as sophisticated....yet.

Have fun!