That was what, almost 3 years ago? It's a totally different climate now, she just hasn't kept up a consistent enough profile for the general audience or radio to care.
You can do constant promotion and be on every talk show, but it doesn't mean that's going to sell your album. Lady Gaga is finding that out the hard way. There needs to be some type of positive buzz and momentum to sell your product, and obviously the singles/album have to be at least half-way decent. Neither she nor Britney really has any of this at the moment. Granted, Gaga isn't flopping as badly as Britney is, but still under-performing and making her label lose money on the album nonetheless.