Actually, they're both dead. They just haven't fallen down yet...
What happened was Blue Ray... and numerous problems with DRM (digital rights management) and the squabbling between just about every Japanese electronics company you can think of...
Steve Jobs said: Blue Ray is just a bag of hurt. (He wasn't too happy with HDMI either!) He had enough and killed development—all of it. New Macs don't even have the DVD drive anymore and there will never be a BD drive. The way technology is progressing, it is my opinion that BD and DVD will not survive. You can get a better, more superior quality with smaller file sizes and players like Roku, etc. and Apple TV etc. (I have a cheap "IncrediSonic" player and the quality of 640x360 h.264 videos is easily on par with DVD quality on an HD tv set [or better].)
I was keeping up to date with DVDSP and the last version I have is 4.2.2. If you require DVD authoring, it may help you if you have an older Mac running Snow Leopard (which was the version of OSX on my 2009 iMac when I bought Final Cut Studio 3) up to about Mountain Lion to run DVDSP on. I've read that DVDSP runs "fine" under Yosemite, but I cannot personally confirm that for you (I can open it, but I haven't put it through its "paces" in years.)
You can do "real authoring" DVD Studio Pro. DVD Studio Pro is about the only software package for Mac that I know of that allows you to actually "program" the disc with instructions (like many commercially created DVDs — animated menus, hidden layers, etc..) Everything you've ever seen a DVD do, you can create in DVDSP. If you have Motion 4, you can import motion projects into DVDSP for use in creating DVD menus and such. It is a very complete development app for the media. I was happy to have it — except — I never could equal the render quality with a 1 hour DVDSP created disc that I could get from my Panasonic set top DVD recorder (recording tv shows) even at 4 hours of programming per disc. (Panasonic's DVD quality with upsampling was "who needs blu-ray" — literally.)
I bought FCP Studio 3 mainly for DVDSP (4 years ago now...) I haven't used it (DVDSP) in at least 3 years now. You have to ask yourself "Is it worth it?" Both Apple and Adobe have abandoned DVD (and Blue-ray). Commercial DVDs/BDs are still being made, but you can't even get a decent price on a set top recorder anymore — they're becoming "rare" (Panasonic has stopped development of those boxes, and they were the best.) All of these companies have read the handwriting on the wall, so to speak (or they're the ones writing it!) You can do better with an 8GB SD card (and the right player) media-wise, than you can with DVD...or BD for that matter. [Also consider what effect UltraHD/4K/5K and up(?) will have as time goes on. More nails in the DVD/BD disc coffin.]
In the meantime, iDVD should not watermark your media... I have no idea what is up with that. It's easier to learn and use, shouldn't cost very much and you won't feel as bad when you ultimately abandon it. And it's better than Toast.