Latest info gotten by ZDNET's Mary Jo Foley from her trusted sources at Microsoft is claiming that Microsoft will launch a brand new browser, a light weight browser of sorts, but will have a lot of extension support for added features (kinda like Google's Chrome).
This browser is in the works an is currently codenamed Spartan and we could see a demo of it at the Redmond event on Jan. 22nd where Microsoft is expected to demo Windows Mobile 10 and new Windows 10 features and UI/UX.
It is not confirmed yet if this browser will replace the popular IE which will ironically be celebrating 20 years since its inaugural launch in August.
Who knows, maybe it could be a browser made/designed specifically for Windows 10 mobile devices (tablets & phones), seeing as they will share one OS and it is a light-weight browser, it fits perfectly.
Microsoft is taking a lot of stuff from Google's playbook and making them better.
Which should have a solid view of where Windows and Windows Phone is headed by this time next year 2015.