Haven't used the HTC, so do not take this feedback as a comparison.
When I bought the E61 (non-camera version) around 6 months back, I had to choose between E61, P990i, SE m600, Communicator and Samsung Ming.
The reasons in brief why I chose the E61 (maybe u can cross-check the same with HTC to see if it fulfills these)
1. I wanted non-camera since camera phones are not allowed in a lot of corporates I visit and more so for the board meetings that we have
2. Wanted wifi since my workplace and home is wifi enabled and wanted this feature for easy movement of data(basic data, restricted for certain uses)
3. Needed office editing capability which this phone offers. At times, I load on a presentation and take only the phone to a meeting for the presentation. Sometimes while travelling, if I felt the need to make some modifications to the ppt, I could do so.
4. Big screen. If I had to do some decent amount of work/browsing on the phone, I needed a large screen to avoid straining my eyes. Also at that time, this phone had the highest resolution.
5. Very very typing friendly. This is a huge plus for me when I need to send mails(configured to use my office mail server) giving urgently needed approvals.
It also has some cons
1. I like a slim phone....helps keep it in the pocket without that awkward bulge
2. Had to spend another 1K on a capdase case to protect the phone against accidental drops.
3. Does not use a normal 3.5mm port for headphones (so cannot plug in my fav senns for listening to music....had to purchase a separate adapter for this feature)
4.
I am a business user as you can see and did not want features like mp3 playback capability(the phone's software come loaded with real player), camera or touchscreen (I hate this feature....too long to elaborate here
)
Hope this helps as a short review from a user of the E61