The essential argument of GodHatesShrimp.com is that we should not condemn homosexuality as a sin based on the Old Testament because the Old Testament also refers to eating certain kinds of seafood (including shrimp) as an abomination, yet Christians do not have any problem with eating shrimp or any of the other forbidden foods. Does the "God hates shrimp" argument have any validity? Yes and no.
First, it is important to note that the title "God hates shrimp" is a reaction to a particular group of anti-homosexuality protestors that are famous for promoting the saying "God hates fags." The argument is that if God hates homosexuals, based on the Old Testament Law, then God equally hates those who eat shrimp. The Bible nowhere says that God hates homosexuals, however. There are lists of things that God hates in the Old Testament (see Proverbs 6:16-19), and homosexuality does not make the list. Yes, homosexuality is a sin, and yes, God hates sin. But again, the Bible nowhere says that God hates homosexuals, or that homosexuality is any more difficult for God to forgive.
Back to the "God hates shrimp" argument - is it valid? Yes and no. First, a Christian should never make an argument exclusively using the Old Testament Law. Jesus fulfilled the Law, ending its requirements (Romans 10:4; Galatians 3:23-25; Ephesians 2:15). If you use the Old Testament Law as the sole argument for homosexuality being a sin, you should also declare that everything the Law outlaws to be sin: eating shrimp, wearing clothing of mixed fabrics, sowing different types of seed into the same field, etc. No, Jesus fulfilled the Law. Christians are not bound by the Old Testament Law, but rather are to be subject to the Law of Christ (Matthew 22:37-39; Galatians 6:2).
So, if the Old Testament Law cannot exclusively be used to argue for homosexuality being sinful, why then do Christians believe homosexuality is sinful? The answer is that the New Testament also clearly and explicitly states that homosexuality is both immoral and unnatural (Romans 1:26-27; 1 Corinthians 6:9). The New Testament confirms the Old Testament command against homosexuality, explains why the command existed, and argues for why homosexuality should continue to be considered sinful. What then about shrimp? Does God still hate shrimp? No. Jesus Himself "declared all foods clean" (Mark 7:19). Jesus later confirmed this in a vision to Peter (Acts 10:15). While the New Testament confirms that homosexuality is sinful, it clearly indicates the food laws to be null and void. God never hated shrimp. Rather, God disallowed the consumption of shrimp to distinguish the Israelites' diet from that of the surrounding nations, and likely due to the fact that since they are bottom-feeders, shrimp are really not very healthy.
What should be learned from the "God hates shrimp" argument is that we should use the word of God consistently, "rightly dividing the word of truth" (2 Timothy 2:15, NKJV). As New Covenant believers, we are not to use the Old Testament Law as the exclusive basis for our morality. Rather, we are to study the whole counsel of Scripture and live accordingly.