I've got both boxes. Not seeing a whole lot of advantage with the Roku 2. In fact I'm a bit disappointed with it.
My opinion of the Roku 2 is in agreement with yours. I own one Roku 2 XS unit, two Roku XD|S units, and previously but gave to a friend, one Roku HD-XR unit. Besides being uglier than the previous units, in many ways the Roku 2 XS unit appears inferior to the Roku XD|S units. The Roku XD|S units rarely have problems with any channels whereas the Roku 2 XS has problems with several channels; e.g., JustinTV. The Roku XD|S unit's non adaptive streaming functionality of the Netflix channel is much more to my liking than the Roku 2 XS unit's adaptive streaming. And wireless Ethernet with the Roku 2 XS unit has been a no-go since day one of its installation; wireless Ethernet has never been a problem with the Roku XD|S and HD-XR units. Oh, well. Patiently waiting for a firmware fix too.
On the other hand, I have to give Roku a bit of praise on all their units.
I recently purchased and installed a Netgear NeoTV NTV200-100NAS. What a major disappointment! Extremely slow in response. After the main screen, the unit's UI gets really sucky. Its selection of channels is not that great. And I have to press its remote control's buttons several times before the unit will react. Compared to the Roku units, the Netgear NTV200 is a complete waste of eighty bucks.
I also own a Sony SMP-N100 and a Sony DMX-NV1 (all my televisions are old Sony models). Both units work rock-solidly, but their UI is horrible to navigate and their selection of channels is poor and limited. Against the Sony units, Roku wins the gold in contests of UI and channel selections.
So, in the end, in my opinion, despite all their flaws, the Roku units are the best stand-alone Streaming Player boxes on the market today. But still, the Roku 2 XS is a disappointment compared to the Roku XD|S.