According to a few things I've read it appears that Sun is pushing Java ME (formerly J2ME) towards being Open Source.
If so, this is extremely important in terms of handset software going forward. Most mid-to-high end GSM phones feature a Java Virtual Machine, typically used for games, and a few additional applications like dynamic UIs. Generally, Java has been a "limited success" - generating revenues & establishing an ecosystem, but without much success in extending beyond a confined games-oriented domain. At one point in time, various companies were talking up full Java-based operating systems (Coincidence: I got a PR email from SavaJe as I wrote this post), but these have not really got any traction.
An extremely sore point among handset manufacturers has been the need to pay a royalty to Sun of (historically around $0.50-1.00 per phone, I believe), on top of the cost of the JVM itself. While this doesn't seem like much, it is a significant fraction of a phone's total "bill of materials" and hence a major impact on the price and achievable margin on the device. In addition, the fragmentation of the way in which J2ME is actually implemented on phones has landed developers, operators, and device vendors with myriad headaches in porting software across a whole range of handsets. Companies like Tira Wireless have closed the gap with specialised porting tools, but it's still been a bone of contention.
This move may particularly benefit Motorola, which has been focused on hybrid Java/Linux software platforms for some time. This article quotes a senior Moto exec gushing enthusiastically about the move. I think it's a negative for TrollTech, which is aggressively trying to evangelise the "pure Linux" approach to phones & sway developers away from other platforms.
Overall, I think this move has the potential to entrench Java more firmly in future handsets at a time when its future was looking shaky - especially as this is a critical time as the industry moves towards more sophisticated handset platforms employing IP/IMS connectivity, multi-tasking and web-type functions.