It appears that Windows Phone will cross the line to not only being on par with iPhone and Android but will start to cross the line to overtaking these platforms (?) with the "Mango"/ 7.5 release of Windows Phone. Someone has mentioned that it appears like a "dam has broken" related to new features coming with this release.
I wrote one my most read blog articles about what I like and dislike about Windows Phone 7 here and I need to say that it appears that the "Mango" timeframe update will not only cover all my concerns, but also go beyond.
"Mango" Watch Feature List:
-Multitasking/ App switching
-Twitter integration into People Hubs
-Live Messenger integration into People Hubs
-Skydrive integration to Word, Excel and Powerpoint (OneNote currently)
-Bing Image Search
-East Asian Languague Support
-Microsoft Lync Client (wahooooo!!)
-Turn by Turn GPS Directions with voice guidiance
-Voice to Text: sms dictation.
-Bing Audio: (Shazam built into Bing?)
-Bing Vision: Image scanner that detects barcodes, Microsoft Tags, QR codes, CDs, DVDs, Book and even text using OCR!
-And with all the hoopla I can't forget to mention Skype is coming as well.
-Visual Voicemail (Source)
-Channel SMS Through Live Messenger or Skype Automatically if available (Source)
-WP7 Can act as a USB drive (Source) (unofficial)
-Facebook chat, AOL chat, Live Mesenger chat integrated into WP7 messenging (Source)
-Group Messenging: create a group that works with SMS or email (Source)
-More Power Saving Settings (Source)
-Native Check-in's (Facebook) (Source)
-WIFI Hotspot support (Source)
-Camera shutter sound control (Source)
-Smart DJ (Zune HD feature (Source)
-Half-way support for Private App distribution (Source)
05/21/11-Microsoft Outlook Tasks on WP7 (according to twitter user WindowsPhone8)
Excellent pictures of Bing Audio, Speech to Text: