I'm not quite sure what the 'vibe' on the street is (and by street, I don't mean wall street, they're like headless chickens riding a herd of sheep). So far I think reaction is mostly neutral or 'wait and see'. The open source community is up in arms fearing a mySQL death blow. I think that fear is unwarranted at this time, and I'm not alone in that thought. I think there could be some real upside to Sun customers, especially Sun/Oracle customers. Oracle brings financial stability and customer base to the table. Sun brings a recently invigorated streak of innovation and solid hardware creation & manufacturing skills.
It would be interesting to see what kind of oracle appliance the combined team could come up with. I have visions of an appliance based on the T5240 that auto-configs via the enterprise manager grid control. It woud ship pre-installed with RAC and the Fusion stack. You plug it into the appropriate VLANs, it attaches to the grid and then you tell it what kind of work you want it to do. It'd have 128 threads, a good mix of disk and memory. If you're starting to run out of capacity, just add another pre-packaged building block to the grid. The devils always in the details, but I think it could work. It'd be a bear to patch/upgrade unless it was built into the process to automatically segment the grid into upgraded vs non-upgraded and once a threshold of nodes are in the upgraded status, switch traffic to those nodes en mass. Because no one else builds a T2 based server, you'd have to get all your kit from Oracle which could drive future revenue. If they make the entry point easy enough and the OS/Hardware simple enough, smaller businesses could run oracle products than before.
Oracle (which owns most of the products I encounter in my professional life these days) could optimize and integrate the Solaris kernel to provide added speed and flexibility on Sun hardware. Especially in regards to performance and scalability. If Sun can optimize it's kernel for the Oracle RDBMS or Java for the Fusion middleware stack or Weblogic with out customizing the respective products, it could be a big win for Oracle. I think the trick is going to be to not customize the products. If they do, they open themselves up to the same anti-trust talk that Microsoft faced. We're a long way away from that, but they wouldn't want to give their competition any ammunition. There was a time when the VOS (Veritas, Oracle Sun) stack was the way to go if you needed to scale big. They even created a joint center for a while to work on issues up and down the stack (not sure where that ever ended up). But there's only so much a joint operation can do, because patents and IP rights get in the way. The barrier between two of those three has just been removed (and the 3rd isn't as vital as it once was).
The other area I like is the cutting edge areas. For example Sun's doing a lot with Flash storage and mixed flash/disk storage. What if you could optimize the database to take advantage of that mixed storage pool? Oracle and a native ZFS pool? And perhaps most interesting (and the one that gets me giddy) would be native DTrace providers for Oracle products. Imaging the diagnosis option if you can natively probe an underperforming SQL query? Probe a 'lost' tuxedo session? And then the gui's that could be written to take advantage of the providers? You'd never buy Spotlight again.
Perhaps the most important reason I like the purchase is Sun survives. I selfishly want Sun to live on because I consider myself to be quite good at Sun. I'm fair at AIX and Linux, but Sun and Solaris is in my wheelhouse. I'm not adverse to AIX or Linux, it's just not what I've had the most exposure to. If Solaris goes away, I guess I'd have to go with Linux because I can run that on just about any hardware. AIX requires me to buy something from IBM.
At any rate, I'm glad Solaris lives another day.