Will the  HTC Evo 4G seriously compete with the next iPhone?

For some customers, yes. For example, my dad wants it badly, more than the iPhone. Why?

* He needs Sprint, so an iPhone is a difficult option for him until the exclusivity with AT&T is over.

* He likes the 4G speed. Now the iPhone 4G might support something fast once announced (a Sprint iPhone "4G on 4G" ??), but so far that is not the case.

* The device is supposed to support tethering via bridge to 802.11 out of the box. He currently does this with WMWiFiRouter on his Treo 800w and loves it. He travels frequently with my mother, this lets them ensure both their laptops have Internet access. Yes, he could buy a Sprint Overdrive — he may still do that — but he'd rather just fold that into his phone.

* He's not overly impressed by the iPhone interface. He does a lot of email on the phone and leaves web browsing mainly to his laptop. So he prefers physical keyboards, a start screen that shows your appointments & messages, etc. He really likes the Windows Phone "Today" screen with your appointments, emails, etc. at a glance.

The Evo doesn't have a physical keyboard but he'll overlook that for the 4G tethering.

* He doesn't have many iPod Touch apps, although he does have an iPod Touch. So far even the sports themed apps (e.g. MLB At Bat) have failed to resonate. That being said, if a phone can stream live video of Purdue games, it will be his favorite thing ever.

How well does Android work with Microsoft Exchange?

I have found no issues running Exchange with Android 2.2.  It will drain your battery faster due to the constant push/pull of information.  You will most likely have to work with your Exch Admin to make sure you are enabled for Active Sync. Coming from a BlackBerry I can say that key features like custom ringtones per sender, subject, etc are missing which is why many people choose to use Touchdown.  Touchdown will also work for you if you have an older Android OS but as Chris said the integration is not optimal.  You can always download the Touchdown trial and compare.

Should I switch from my HTC Touch Pro 2 to the iPhone4? Is access to the AppStore the only functional benefit?

Read this review:  http://www.engadget.com/2010/06/…

It is the definitive guide.  And, yes, absolutely, you must have an iPhone4.

How does the HTC Incredible perform as an MP3 player in relation to the de facto iPod capability of the iPhone?

I think it depends how you use your phone and what you expect out of the media player.  The stock Android media player takes alot of flack but personally I can't see why (coming from an iPhone).  It has a fairly simple interface, a good homescreen widget, it's responsive and plays music.  These are the only features I want from a music player.

The little touches mentioned in Michael Whalen's answer are valid, I'd also add the nice home button double tap for media controls on the iPhone being particularly cool.  However the Android player also has some useful features, it's more pluggable for example. Using the last.fm service and attaching a scrobbler for Android is a free, painless experience.  That wasn't so easy to achieve on my iPhone. It's also nice to be able to utilise Dropbox to sync up some music between friends and phone.

I'm not saying one is better than the other, both have their pro's and con's.  Like Michael correctly says though make sure you get a good play with both.  You want to make a semi-informed choice if you're going to be stuck with it awhile 🙂

What are some good bike mounts for the HTC Magic?

Try this guy from RAM: RAM EZ-ON/OFF™ Bicycle Mount with AQUA BOX® Pro 20 Case It was a waterproof holder that lets you use the touch screen and side buttons. Should definitely fit an HTC Magic. You can also shop around on their website to find more options and build your own custom mount by selecting a waterproof case, arm, and bike base.