922 graphics will not trickle down to older STB's. That is Dish's official statement. However, While the Dish UI isn't the best, it is very good and many former Direct TV subs say that the Dish graphics/UI is better. One thing they do mention is that some like the info as part of the banner on Direct rather than the majority of the screen on Dish. But overall they do like it better.
No, Tivo screens are the richest looking with animation, however the Tivo guide is crap compared to the Dish grid guide--and no, the TV Guide grid display on Tivo is even worse than the Tivo guide.
Dish has always been a service focused on technology of the system, features (PIP, external HDD, etc.), ease of use (a lot of seniors are Dish subscribers) and support of multiple satellites and services (a ton of internationals) and the best DVR's they can produce without violating patents (Tivo lawsuit yet to be resolved). It has taken all these years for Dish to even get around to having channel logos on the guide with the upcoming 922. But I think Dish subscribers always valued these innovations more than the most "cool" looking graphics. The 922 sounds like the box for you if you value the most "dazzling" UI. Honestly, I want the 4 stream recording capability of the 722K (2 OTA tuners) a heck of a lot more than a UI facelift. Capabilities are what really counts.