They have the same meaning. We use 'seem to be something' or 'seem to be like something' to mean 'give the impression of being or doing something'. You seem (to be) a friendly person. (British English) Americans do not say 'You seem a friendly person'. They use 'to be' or 'like' after these verbs: 'appear', 'look', 'sound' and 'feel': You seem to be a friendly person (or 'You seem like a friendly person') = American English It seemed a good idea. (British English) It seemed like a good idea. (American English)

They both mean pretty much the same thing. The second form is almost always used, even though the first is technically correct. There is a subtle twist of meaning here. If I really wanted to compliment a person on being friendly, I would say "You're pretty friendly" or "You're really friendly." If I say "You seem like a friendly person." the meaning conveyed would be that the compliment is qualified - yes, you seem like a friendly person, but you might not actually be one. This applies to both the forms above.