I'm definitely disappointed that the sd card and 4g isn't working yet, and also that Google has not released the source code for Honeycomb. In fact I'm downright pissed off about it. I bought my Xoom believing that it would follow a similar course as my Droid did. I expected the hardware to be completely working in a reasonable amount of time, and then a pretty much full exploitation of all the hardware & software to follow in it's own time as developers released better and better ROMs.
That's not happening yet, but I believe it will soon; -Soon enough where my 4g Xoom sporting a kick-ass ROM will outperform most new tablets as they come out of their boxes. It's why I bought it. If I had no intention of rooting it and installing a custom developed ROM on it, I probably would've bought a cheaper tablet.
But I sympathize (very much) with those who did buy a Xoom, never intending to have to root it just to get the promised functionality, who have become too frustrated from the wait, especially as new tablets are expected to be released soon boasting better features (or on par with) than the Xoom, for less money! I mean, as a consumer, how is this not a kick in the teeth that our sd card slots have to be hacked (...thus voiding the warrantee) just for our

tablets to be
almost as functional as they were advertised to be?
I LOVE my Xoom, and there's no way I'm getting rid of it. In fact, if I dropped it down the stairs and killed it, I'd go blow nearly all of my pay check on a new one that same day. Does the screen suck? -No, it does not. Does the build quality suck? No, it does not. Does it suck at anything that it's supposed to do? The only thing I can think of is that it sucks at making Motorola look good. Other than that, it's a great tablet that's still going to be great for flashing that perfect ROM onto.
It all (always) comes down to"application".
Intend to root/hack/flash an Android tablet? The Xoom could be perfect for you.
Intend to leave it stock? Maybe you should look around a bit before choosing the Xoom, as there are other tablets that offer better functionality right out of the box.
Want perfect graphics from a perfect screen? You might be asking too much from any tablet just yet.
No matter what, if you don't bother to do your research before dropping several hundred bucks on some fancy glass, you're being foolish. That's the difference I see between Xoom owners disappointed about the hardware & software delays, and those disappointed in the tablet itself. The two different reasons should never be in the same thread, but they almost always are.