Well, I sure hope not. Mainly because I have five of them, but also because that would mean v1's ,v2's, p1's p2's Mothra, Oceangotchi, Angelgotchi... and everyone else is too! Which I think is crazy talk, because I want one of all of those!
So no, just because someone doesn't talk about Billy's Mom doesn't make her out of style, so to speak.
Okay... so what does this have to do with a new Tamagotchi you need help with? This forum is for new Tamagotchi owners who need help figuring out their Tama(s). Perhaps this should be in the What's On Your Mind? section.
Anyway, on-topic...
I totally agree with PeaceSign. Just 'cause nobody talks about 'em anymore doesn't mean they're out of style. I have a V3 and love it! Maybe people just don't have any problems with their V3, or nothing new happened to them.
If you must have evidence, look in the Tama-Logs forum in the Library. I'm sure you'll see tons of logs with V3's in them.
Besides, if the older Tama versions went out-of-style, then the V4 and V4.5 would be out-of-style as well, wouldn't they?
Its not out of style, people just don't talk about them because there are newer versions they need to explore and cover. I like the v3, it has access to Tamatown and it doesn't have all the jobs and family stuff.
People don't talk about them more because all the newer versions are coming out. I would sure hope that they're out of style though. Because, V3's are the second best regular version out there! (next to V2)