Excepting, of course, that the online Character Builder includes ALL and EVERY current rules addition, edition, and inclusion to date... and you can't easily filter out what the DM says is not fair game for his campaign.
The offline Character Builder had a handy "configure" page, allowing you to quickly and easily filter options by source. Narrowing it down to the "Core 3" only, or indeed whatever other set of sources you wanted, was child's play. I would be surprised if the online CB doesn't contain a similar option.
What
would be nice would be an option for the DM to set up a more detailed profile for his campaign that allows much greater control over options (perhaps he doesn't want Dragonborn, for example). The system would of course need to allow the DM to export that profile and send it to his players for their later use.
(I'm not sure how much work that would actually be. Certainly, I consider it a "nice to have" rather than a "must have" feature.)
[MENTION=22424]delericho[/MENTION], maybe this is my inner grognard speaking, but the idea of Shardminds and Warforged joining Dragonborn and Tieflings in the Player's Handbook is borderline nauseating to me. Actually, having the Dragonborn and Tiefling in the first PHB is one of the mistakes that WotC made with 4E, imo. Yeah I know, they were trying to appeal to the "WOW crowd," but they forgot that a bird in hand is better than two in the bush and all they did was lose the bird in hand...thus Pathfinder.
I once thought as you did. I was particularly annoyed by the comments that "Gnomes don't really have a niche", which was definitely untrue (trickster).
But...
The truth is that when 4e was released with the Dragonborn and Tiefling in place, the world didn't end. It was easy for groups to just ignore them if they didn't want them, and DMs
always had the power to ban them. And WotC very quickly moved to support the 'missing' races, so that wasn't an enormous issue.
The Dragonborn and Tiefling are popular - more popular than either the Gnome or the Half-orc were. They are interesting races, each with their own character, and they genuinely do bring something to the game. (The same would be true of the Warforged and the Shardmind, IMO.)
If I were doing a 5e PHB, I would
definitely drop the Eladrin and the Half-elf from the list of races. I can certainly see an argument for restoring the Gnome and Half-orc in their place. But, yeah, I think the Shardmind and the Warforged just have a stronger claim at this time.