WhatHappened since 2002 for this material? Is it deprecated in favor of something new?
MIDP is a set of Java APIs intended to be implemented in 'mobile information devices' (e.g. mobile phones), providing a limited Java runtime environment in which downloaded applications called 'MIDlets' can run. MIDlets are typically rather small; some devices limit them in size to as little as 30KB. The first MIDlets available are mostly small arcade-style games, but many other types are possible. For a good sample and an idea of what's possible, see http://www.midlet.org.
MIDP includes APIs for:
UI (based on Screens, of which only one may be visible at a time)
Canvas - draw what you like on it (suitable for games)
Form etc. - WAP-like screens with text items, text fields, images, etc...; adapted to device UI style
Persistent storage (byte-array records with integer keys, stored typically in Flash memory)
Networking (at least HTTP client capability, based on CLDC's 'generic connection framework')
Only HTTP client functionality is mandated (i.e. request; response)
Mobile network bandwidth & latency is significantly different to fixed networks; beware!
Optionally e.g. TCP/IP sockets, UDP datagrams, HTTP servers etc. may be implemented, but that's unlikely if the transport is WAP
Application model ('MIDlets', quite similar in style to JavaApplets?)