|Let's see, if memory serves, the first announcement about an Intel OEM "offering and supporting" Solaris on their boxes was made in 1991 by what was then called SunSoft, the software "planet" of the ill-fated and relatively short-lived reorganization of Sun into specialized business units for hardware, software, printers, service, etc. Actually Eric Schmidt ran one of these "planets" at the time, reporting to McNealy.|
In fact, in 1991 Ed Zander, who ran SunSoft, put together a whole lineup of OEM's who got up on a stage before a few reporters and in effect said "sure, we don't care if another operating system is available on our boxes, as long as it doesn't cost us anything to develop or distract us from selling the important stuff".
The announcement in the long term yielded negligible revenues to Sun judging from publicly available data. The important stuff for these OEM's was Windows. And besides, the same OEM's said pretty much the same thing about SCO Unix at the time (which might well not be the case this go-round).
This present HP announcement is not only a non-event, it is the stale and desperate echo of a prior 18-year-old non-event. An announcement like this means something if and only if a substantial purchase order from HP to Sun is connected with it. Endorsements are worth (your favorite uselessness metaphor goes here).
Time will tell what they actually "plan to work on".