Hi there!
I just upgraded my home RB150 from rc13 to 3.3 by drag and dropping the routeros-mipsle-3.3.npk into “Files”.
Rebooted, everything fine, but since the upgrade my Winbox title bar says: “admin@192.168.7.254 - Winbox v3.3 on RB MR (powerpc)”
Hmmm, did the software upgrade change my platform or is it a tiny bug? 
Greets,
uebi
Hmmm, something else I just realized:
I had some policy routing configured in 3.0rc13 that know no longer works 
The rules where that port 80 and 53 go out one upstream and everything else through the second upstream. There is also a more specific route that port 80 for a smaller network always flows through the second upstream. Worked like a charme, but now I get a timeout if I try to access a webserver in this network. As soon as I disable the more specific route I can reach it over upstream 1. If i try it on a second RB (532) with 3.0 it still works.
Did anything change for policy routing/routing marks?
Greets,
uebi