My guess - new devices will use a standard JVM, but J2ME will live on much longer than its expected lifetime. Exactly how long I don't know - it depends whether Java progresses downwards into watches and Tamagotchi-like toys, IMHO.
Look at WAP - when it came out it was deemed the next big thing, and everyone rushed to get on the bandwagon. One critical look at the system told you that it would be redundant within 18 months as portable devices would be powerful enough to handle normal HTML by then, and the drive towards XHTML was doing away with the need for a full SGML parser in any case.
But WAP is still very much around, more due to the number of legacy devices and the fact that it's now considered quite mature, than to any real technical merit.
Lots of new devices will support full JVMs, but there'll still be J2ME content out there. There'll also be lots of devices around that are too old to handle a full JVM, so J2ME will still be the only way to deploy Java code to them.
Newer, less powerful devices on par with today's medium- to high-power devices will then be able to take up the J2ME banner.
YMMV, IMHO etc.