Sony Ericsson has been inviting journalists to a Mobile World Congress kick-off party (to be catered by world-famous elBulli restaurant) on the opening night of MWC next Monday.  In typical SE style, the invitation features the headline "I [SE Logo] big ideas."

Rumors are flying all over the Web today that SE's big ideas aren't just new handsets, but rather an entirely new line of mobile phones to be unveiled Feb 10th, the day before MWC starts.  The G-Series will reportedly be a line of "compact" touch-screen devices launched with the G900i and G700i.

If you believe the rumors, get ready for a G900i (code-name "Tyra") with a 2.6" touchscreen, 5MP camera, and integrated WiFi, and a G700i with a similar display and 3.2 MP camera, but no WiFi.  SE is also rumored to be taking the wraps off of some new accessories this coming Sunday, as well.

Now these latest bits mention nothing about the long-rumored P5i smartphone, hailed as SE's "iPhone Killer" when it was still cool to call every new high-end handset an iPhone Killer.  Sony Ericsson's current flagship model, the P1i, is a Symbian UIQ-based smartphone featuring both a touchscreen and a QWERTY keypad.  Could a QWERTY-enabled P5i and a pair of QWERTY-less G-series devices all be on tap for next week?  That'd make for one blockbuster of a show for Sony Ericsson.

Check out our source at SEfanatics.