Have you tried Google Voice yet? Well, if you live in the States, you should. You really must sign up for an invite.
It takes about two weeks for one to arrive. I think Google is simply being caution about rolling out one of the most anticipated features of its web apps, if you can call it that.
But I think Google should eventually make Google Voice a standard feature in Android wherever Google-branded phones and mobile devices are sold.
I've been using GV on my G1 and, I have to say, this is the missing app for me. Along with Meebo that now does a decent job of staying connected with my IM contacts, GV has really done a good job of making you feel like you're connected to your friends, family, and work contacts.
So, if you haven't already, get the GV app and secure yourself a Google Voice number. Here is the link where you can go get one.
Now, I'm just waiting for Google to push SMS and visual voice mail notifications. Anyway, while I love my iPhone, I think Android can be just as good if not better since Google isn't likely to interfere with app store politics as much as Apple's more Stalinistic approach does and Android is perceived to be more open (open's definition being arguable).
Note: There are a couple of scripts available for setting notifications to your gmail to tell you when you have an sms notification. Right now, you can get notifications whenever you get a voicemail. Still, push works better, don't you think?