I guess that depends on your skill. I'm looking forward to it.
Literal
That [topic-は] your arm-depending [conjecture-かな]. Expecting [emphasis-よ].
腕 ('arm') is metaphorically used for 'skill, ability' — a body-part idiom. 腕次第 combines 腕 with 次第 ('depending on'), giving 'depending on your skill.' 期待する ('to expect, look forward to') in ~ている form marks anticipation as an ongoing state. かな softens the conjectural claim with a touch of playful suspense.