Oh no! That's the best thing! Of course e-mails should not be in the same place as SMS and IM as they're usually much, much longer than the average SMS or IM message, but SMS and IM in the same place is wonderful. They're still the same people you're talking to, and it's ridiculous to need 10 apps opened at the same time if you have contacts on 10 different services. (Imagine having to do that with the current auto-closing behaviour!)