You really don't need to offer reviews in exchange for reviews I give. I mean, sure, it's nice, and I could really use the reviews, but you don't HAVE to give them.
Similarly, if you do offer reviews in exchange, please, please, PLEASE follow through. I'm not asking for anything as large as what I'm giving. Feedback on a single thing to improve it, or just saying "I like the song, I can't think of any way I'd improve it" would be fine.
I'm not going to name any names here. But several people have promised reviews, said they'd do it in the next few days, or they were working on it currently (so that assumedly it'd be done in the next hour or two), and then never followed through. If you're going to give a review, give a review. If you aren't, that's fine - just don't tell me you will.
Hopefully I'm not coming across as rude to the people this applies to. It's just been bugging me lately.