They didn't really even bother getting her to speak Spanish here: (she tried one line — with a mistake — and was like, "How was that?"). From the clip in TreeHouse's answer, you can tell a few things:
- She doesn't properly group words. For example, at one point she says "de un" as two very distinct words with a break in the airstream, whereas a native would say "deun" as a basically a single word.
- Her vowels are still noticeably influenced by English which in their basic forms are generally diphthongs (where as Spanish's base vowels are all monophthongs). For example, words ending in -o she tends to pronounce as -ou
- Cognate words and names she switches quickly back to an English pronunciation (see how she pronunces Univision in Spanish, basically like an English speaker would)
- She pronounces the Z as we would in English, when the correct pronounciation basically an English S or TH (as in thistle) (depending on dialect, from her, we'd expect S)
Also, in the music clips you provided, the autotuning is very strong and that makes it harder to judge intonation and such (and also makes it sound weirder to those of us not used to overproduced sound)
Songs can be great for practicing pronunciation — especially understanding how to pronounce "between the words", but you'll want to try stuff from actual native speakers that is a bit slower. Gloria Estefan's early stuff is great. Julieta Venegas is a good current artist. I did really well with a number of Tontxu's songs since he's in my vocal range and I could sing it in the car better :-)