It is odd in the sense that she's putting you on the spot, assuming that you will write a positive review of her in hopes of winning more business.
I have had conversations about being a member of TERB and a girl will say, "Feel free to write a review". To that, I will say it's personally not my thing and that I don't kiss and tell. It's not the truth but what else can you say at the moment?
If you only had a 'good' session, there's really not much point in writing a review anyways. If she has good cred already, one mediocre report won't affect that and it's not worth your time...might have just been a case of chemistry or mood you were in.
Now if she was bad, that's a different story. Some girls provide great service to start and then mail it in after due to either apathy, or bad experiences providing certain things. That's when you need to refresh the earlier reviews with an up to date status.
I saw one girl twice, a year apart. The first time she was awesome...BBBJ, DFK, and really into it. 12 months later it was CBJ, no kissing at all and she offered greek (which wasn't on the menu before), but wouldn't go there that night. She was marketing herself as 'no restrictions' but had much more restrictions than she did the first time I was with her. It was disappointing and you could tell that her time in the business had hardened her.
Sometimes though, mediocre service isn't enough to write a bad review. There's some nice girls out there that are just ok, so not writing a review at all can seem like the best thing to do.