Pricing involves a 1-time $0.99 per song upload fee, plus an annual $7.98 per album fee (an "album" is defined as any music submission, whether an actual album or just a single song, that was uploaded at one time. If you upload 7 songs separately, you’ll be paying for 7 "albums" every year). TuneCore also penalizes artists $20 if they remove their music less than 6 months after uploading it.
I’d be more interested if TuneCore offered a guaranteed, faster submission process. Submitting directly to iTunes is free, but can take a while, and you’re not guaranteed inclusion or even a response. No mention of any timeline is made on TuneCore’s site.
iTunes is #1 in terms of music download sales, so TuneCore chose their focus market wisely. However, be sure to compare what they offer with The Orchard and IODA before making your decision to upload your music for distribution.